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Hexafluorosilicic Acid Version 2.0 AGROPOLYCHIM JSC Date of issue: January 2011

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SAFETY DATA SHEET

Hexafluorosilicic Acid This Safety Data Sheet contains information concerning the potential risks to those involved in handling, transporting and working with the material, as well as describing potential risks to the consumer and the environment. This information must be made available to those who may come into contact with the material or are responsible for the use of the material. This Safety Data Sheet is prepared in accordance with formatting described in the Regulation (EU) No 453/2010, and described in CLP Regulation (EC) No 1272/2008. Section 1. Identification of the substance/mixture and of the company/undertaking 1.1 Product identifier Chemical Name: Hexafluorosilicic Acid CAS Number: 16961-83-4 EINECS Number: 241-034-8 REACH Registration No.: 01-2119488906-19-0000 Chemical Constituent: Monoconstituent inorganic 1.2 Relevant identified uses of the substances or m ixture and of the company/undertaking Used in mixing, preparation and repackaging, as an intermediate in the synthesis of chemicals, as a

processing aid and in cleaning and disinfection. It is also used in fluoridation in water treatment, metal surface treatment, and manufacture of basic metals, mineral acidification, professional cleaning and disinfection and as a laboratory chemical.

1.3 Details of the supplier of the safety data shee t Manufacturer:

Company name: AGROPOLYCHIM JSCo Address: BULGARIA, 9160 DEVNYA INDUSTRIAL ZONE Contact person: eng. Miroslava Tsvetkova Engineer chemical process Production Department e-mail: [email protected] tel: +359 / 519 97 416, fax: +359 / 519 933 63 1.4 Emergency telephone number In case of emergency:

Country Contact Number Specific Information Austria +43 1 40 400 2222 General number Belarus +375 (0)17 201 9158 Belgium +32 70 245 245 Available 7 days a week,

24 hours a day Bulgaria +359 2 9154 409 Croatia +385 1 234 8342 Czech Republic +42 2 2491 9293

+42 2 2491 5402

Denmark +45 82 12 12 12 Public phone number. Number for use by the public. Available 24


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hours a day, 365 days a year. Name, social security number and telephone number will be requested.

+45 35 31 55 55 Number for health personnel for the treatment of poisonings.

Finland +358 9 471 977 Open 24 hours a day. Gives advice on prevention and treatment of acute poisonings.

+33 (0)2 41 48 21 21 Angers - Open 24 hours a day, 7 days a week

+33 (0)5 56 96 40 80 Bordeaux - Open 24 hours a day, 7 days a week

+33 4 76 76 56 46 Grenoble – Toxicovigilance centre. Open 24 hours a day, 7 days a week.

0 825 812 822 Lille - National number - Open 24 hours a day, 7 days a week

+33 (0)3 2016 0824 Lille - International number - Open 24 hours a day, 7 days a week

+33 (0)4 72 11 69 11 Lyon - Open 24 hours a day, 7 days a week

+33 (0)4 91 75 25 25 Marseilles - Open 24 hours a day, 7 days a week

+33 (0)3 83 32 36 36 Nancy - Open 24 hours a day, 7 days a week

+33 (0)1 40 05 48 48 Paris - Open 24 hours a day, 7 days a week

+33 (0)3 26 06 07 08 Reims - Toxicovigilance centre. Open 24 hours a day, 7 days a week.

+33 (0)2 99 59 22 22 Rennes - Open 24 hours a day, 7 days a week.

+33 (0)2 35 88 44 00 Rouen - Toxicovigilance centre. Open 24 hours a day, 7 days a week.

+33 (0)3 88 37 37 37 Strasbourg - Open 24 hours a day, 7 days a week.

France

+33 (0)5 61 77 74 47 Toulouse - Open 24 hours a day, 7 days a week.

Georgia +995 99 533320 +49 (0)30 450 65 35 65

Berlin

+49 (0)30 19 240 Berlin - Available 24 hours a day

+49 (0)228 287 3211 Bonn +49 (0)228 19 240 Bonn - Available 24

hours a day

Germany

+49 (0)361 730 730 Erfurt


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+49 (0)761 19 240 Freiburg - Available 24 hours a day

+49 (0)551 19 240 Gottingen - Available 24 hours a day

+49 (0)6841 19 240 Hamburg/Saar +49 (0)6841 19 240 Mainz +49 (0)89 19 240 Munich/Munchen +49 90)911 38 92 665

Nurenberg

+30 10 779 3777 Greece +30 231 0999221

Hungary +36 80 20 11 99 +354 525 111 Iceland +354 543 2222

Ireland +353 1 8379964 Available 24 hours a day, 7 days a week

Israel +972 4 854 1900 +39 03 526 9469 Bergamo +39 051 647 8955 Bologna +39 095 25 4409 Catania +39 054 735 2612 Cesena +39 87 134 5362 Chieti +39 055 794 6150 Florence Firenze +39 10 352 808 Genoa Genova +39 18 753 3296 La Spezia – General

Telephone number +39 0832 68 5374 Lecce +39 02 6610 1029 Milan Milano +39 081 45 9802 Naples Napoli +39 03 822 4444 Pavia +39 0434 399335 Pordenone +39 96 581 1624 Reggio Calabria +39 06 305 4343 Rome +39 06 49 06 63 Centre Antiveleni +39 011 663 7637 Torino

Italy

+39 04 0378 5373 Trieste +7 3272 927055 Almaty Kazakhstan +7 3272 925868 Shimkent

Latvia +371 704 2468 +370 2 36 20 52 Lithuania +370 2 36 20 92

Netherlands +31 30 274 88 88 Norway +47 22 59 13 00 Available 24 hours a day

(English language service provided).

Poland +48 58 301 65 16 Gdansk +48 58 349 2831 Gdansk +48 12 411 99 99 Krakòw +48 42 63 14 724 Lòdz +48 81 740 2675 Lublin +48 81 740 2676 Lublin +48 61 84 769 46 Poznan +48 17 86 64 000 Rzeszow +48 17 86 64 404 Rzeszów +48 32 266 11 45 Sosnowiec +48 22 619 66 54 Warsaw +48 22 619 08 97 Warsaw +48 71 343 30 08 Wroclaw

+48 71 789 02 14 Wroclaw


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808 250 143 National number Portugal +351 21 330 3284 International Number +40 2121 06282 Bucharest – Child cases

only +40 2121 06183 Bucharest – Child cases

only

Romania

+40 21 230 8000 Bucharest – Clinical Toxicology

Russia +7 495 628 16 87 Russian only Slovakia +421 2 54 77 41 66 Available 24 hours a day Slovenia +386 41 650 500

+34 93 227 98 33 Barcelona +34 93 227 54 00 bleep 190

Barcelona

+34 91 562 04 20 Madrid +34 95 437 12 33 Seville

Spain

+34 91 562 04 20 Seville – Available 24 hours a day.

+46 8 33 12 31 International number for acute poisonings. Available 24 hours a day.

Sweden

112 National number for acute poisonings. Available 24 hours a day.

+41 44 251 51 51 International number. Available 24 hours a day.

Switzerland

145 National number for Switzerland and Liechtenstein. Available 24 hours a day.

0 800 314 7900 Turkey only Turkey +90 0312 433 70 01 International number 0870 600 6266 UK Only +44 (0)870 600 6266 UK only, available only

to health professionals +44 (0)20 7188 0300 Available 24 hours a

day, 7 days a week for emergency scientific and medical services

+44 (0)20 7188 0199 Use and safety information on Chinese and traditional herbal medicine.

United Kingdom

+44 (0)20 7188 0100 Available 24 hours, provides information on hazards of chemical exposure and advice on treatment of poisoned patients.

Section 2. Hazards Identification 2.1 Classification of the substance Classification under C, R34.


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Directive 67/548/EEC: Classification under Regulation (EC) No. 1272/2008:

Skin Corr. 1B H314.

Physicochemical hazards: No physico chemical hazards are expected. Human health hazards: Acutely toxic following dermal and inhalation exposure. Causes severe burns when applied to human skin. Inhalation exposure results in burning of the eyes and numbness of the lips. Following prolonged exposure, skeletal fluorosis and urinary fluoride excretion was observed in humans. No mutagenic activity is expected. There is no evidence of carcinogenicity following exposure. No adverse reproductive effects are likely to occur following exposure. Environment hazards: Emission of Hexafluorosilicic Acid directly to municipal sewage treatment plants should be avoided as with all acids and fluoride compounds. Potential effects in the environment are alteration of pH and toxicity due to fluoride exposure. Please see Section 16 for full text of each classification. 2.2 Label elements Regulation (EC) No 1272/2008:

Signal word Danger Hazard Statements H314 Causes severe skin burns and eye damage Precautionary statements: P260 Do not breathe dust/fumes/gas/mist/vapours/sprays. P301+P330+P331 IF SWALLOWED: rinse mouth. Do not induce vomiting. P303+P361+P353 IF ON SKIN (or hair): Remove/Take off immediately all contaminated clothing. Rinse skin with water/shower. P304+P340 IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing. P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. P405 Store locked up. 2.3 Other hazards PBT: Not considered to be a PBT Section 3. Composition


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Name CAS Number EINECS Number

% Composition Classification according to Directive 1999/45/EC

Classification according to Regulation (EC) No. 1272/2008

Hexafluorosilicic Acid

16961-83-4 241-034-8 >95 % C, R34. H314 Skin Corr. 1B.

Hydrogen fluoride 7664-39-3 231-634-8 3.0% T+; R26/27/28 C; R35

H330, Acute Tox 2 H310, Acute Tox 1 H300, Acute Tox 2 H314 Skin Corr. 1A

See section 16 for full description of the text of each classification. Section 4. First Aid Measures 4.1 Description of first aid measures Inhalation Fresh air, rest. Half-upright position. Refer for medical attention. Skin contact Remove contaminated clothes. Rinse skin with plenty of water or shower. Immediately refer for medical attention. Massaging calcium gluconate or treatment with calcium carbonate into the affected area is recommended treatment. Accidental eye contact First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then consult a doctor. Rinse the eyes with a calcium gluconate 1% solution in physiological serum (10 ml of calcium gluconate 10% in 90 ml of physiological serum). Ingestion Rinse mouth. Do not induce vomiting. Give plenty of water to drink. Refer for medical attention. Treatment with calcium carbonate and calcium gluconate is recommended. 4.2 Most important symptoms and effects, both acute and delayed Burning of the eyes and numbness of the lips may occur following inhalation exposure, with symptoms appearing up to 24 hours after exposure. Skeletal fluorosis may also occur following chronic exposure. 4.3 Indication of any immediate attention and speci al treatment needed. Treatment with calcium gluconate or calcium carbonate is recommended. Section 5. Firefighting Measures 5.1 Extinguishing media Use extinguishing measures that are appropriate to local circumstances and the surrounding environment. Suitable media may include water spray, dry chemical, fog or foam.


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5.2 Special hazards arising from the substance or m ixture When heated to decomposition (1050 deg C), it emits highly toxic and corrosive fumes of Hydrogen Fluoride, Silicon Tetrafluoride and Hydrogen gas. 5.3 Advice for fire-fighters Wear self-contained breathing apparatus and protective suit. Fire fighters must wear fire resistant personnel protective equipment. Wear chemical resistant oversuit. Section 6. Accidental Release Measures 6.1 Personal precautions, protective equipment and emergency procedures Large Spills: Level A clothing (full encapsulating suit with self-contained breathing apparatus). Do not attempt to take action without suitable protective clothing - see section 8 of SDS. Small Spills: Impervious clothing and rubber gloves should be used for small spills. 6.2 Environmental precautions Do not allow any release to waterways, watercourses, drains and municipal sewers. If the product contaminates rivers and lakes, inform respective authorities. 6.3 Method for cleaning up Collect leaking and spilled liquid in sealable iron containers as far as possible. Absorb remaining liquid in sand or inert absorbent and remove to safe place. Keep in properly labelled containers. Keep in suitable, closed containers for disposal. 6.4 Reference to other sections Refer to section 8 of SDS for personal protection details. Section 7. Handling and Storage 7.1 Precautions for safe handling Tanks should be vented and fitted with an overflow pipe. Tanks should be bunded to contain spillage. For smaller packages double skinned HDPE plastic containers are acceptable. Submerged loading should be preferred to avoid splashing. 7.2 Condition for safe storage, including any incom patibilities Store in a cool, dry, well ventilated area away from sources of ignition. Do not store in glass or stoneware. Bulk quantities should be stored in plastic (uPVC, Polypropylene or Polythene) or rubber - lined tanks. 7.3 Specific end use(s) No further details Section 8. Exposure Controls/Personal Protection 8.1 Control parameters Hexafluorosilicic Acid: 95% Hydrogen fluoride: 3.0%


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DNEL/DMEL Worker Industry Professional

Consumer Exposure route

Exposure frequency Critical component

Remark

Not applicable

Not applicable

0.01 mg/kg bw/day

oral short term (acute)

Systemic toxicity from repeated dose toxicity

Not applicable

Not applicable

0.01 mg/kg bw/day

long term (repeated) Systemic toxicity from repeated dose toxicity

Not quantifiable due to corrosive properties

Not quantifiable due to corrosive properties

dermal short term (acute) long term (repeated)

3.125 mg/m3 3.125 mg/m3 1.56 mg/m3 inhalation short term (acute)

Local effects from respiratory tract irritation.

Not derived Not derived 0.04 mg/m3 inhalation short term (acute)

Systemic effects from repeated dose toxicity

Not derived Not derived 1.56 mg/m3 long term (repeated) Local effects from respiratory tract irritation.

1.88 mg/m3 1.88 mg/m3 0.04 mg/m3 long term (repeated) Systemic toxicity from repeated dose toxicity

Workplace exposure limits: Hydrogen Fluoride: UK – TWA (8 hour reference period): 1.5 mg/m3. UK – 15 minute STEL: 2.5 mg/m3. PNEC (freshwater): 0.9 mg/L. PNEC (soil): 11 mg/kg. PNEC (STP): 51 mg/L. 8.2 Exposure controls Ensure there is exhaust ventilation of the area. Facilities are housed outdoors and not close to buildings. The integrity of the enclosed processes are fully monitored. Ensure that primary emission sources are not located in the breathing zone of the worker. Respiratory protection Wear EU approved self-contained acid suit and/or approved respirator. Hand protection Protective anti-acid gloves.


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Eye protection Face shield or eye protection in combination with breathing protection. Skin protection Chemical resistant, anti-acid protective clothing. Section 9. Physical and Chemical Properties 9.1 Information on basic physical and chemical prop erties Appearance: Colourless liquid. Odour: Pungent Odour threshold: n.a. pH: n.a. Melting point/freezing point °C: 19°C Initial boiling point and boiling range °C: n.a. Flash point: n.a Evaporation rate: n.a Flammability Not flammable. Vapour pressure: 2300 Pa at 293K. Vapour density n.a. Relative density: 1.0407 -1.2742 g/cm3 for solutions of 5 -30% and 1.4634 at 25

degrees Celsius for a solution of 60.97%. Solubility: Miscible with water. Partition Coefficient: n-octanol/water: n.a. as substance is inorganic. Auto-ignition temperature: n.a. as substance is inorganic. Decomposition temperature: n.a. Viscosity: 6.5 Pas Explosive properties: Not explosive. Oxidising properties: Non-oxidising. 9.2 Other information No further details Section 10. Stability and Reactivity 10.1 Reactivity Reacts with many metals to produce flammable and explosive hydrogen gas. Keep containers cool with water, using spray nozzles. 10.2 Chemical stability Stable under normal conditions of use. 10.3 Possibility of hazardous reactions Possibility of hazardous reactions occurring at decomposition. 10.4 Conditions to avoid Incompatibles 10.5 Incompatible materials Metals, glass, stoneware


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10.6 Hazardous decomposition products Decomposition will occur at temperatures above 1050 degrees C and will produce toxic and corrosive fumes. Section 11. Toxicological Information 11.1 Information on toxicological effects Acute Toxicity: Acute toxicity will be dominated by local (site of contact) irritant and corrosive effects. Causes severe burns when tested on human skin.

Irritation: Not examined as substance is corrosive. Corrosivity: Corrosive to skin and eye. Sensitisation: Not sensitising. Repeated dose toxicity: No studies have been performed with HFS acid, however comprehensive data are available for sodium fluoride. The repeated dose oral toxicity of HFS acid will be due to fluoride, therefore read-across from the comprehensive NTP dataset with the soluble salt NaF is appropriate. Effects of repeated fluoride exposure in experimental animals were seen on the teeth, bones, respiratory tract and kidney. Evidence from epidemiological studies in humans also indicate that prolonged exposure to fluoride causes dental and skeletal effects. Following prolonged inhalation exposure, increased bone densities and a urinary fluoride excretion rate ranging from 1.0 – 9.6 mg/L were reported in an epidemiological study.

Carcinogenicity: Not carcinogenic based on NTP studies in the rat and mice are available for sodium fluoride.

Mutagenicity: Following in vitro bacterial reverse mutation assay, negative results were observed. An in vitro cell gene mutation assay resulted in cytotoxicity but not mutagenicity while a second cell gene mutation assay indicated positive results in mouse lymphoma cells. Ambiguous results were obtained in an in vitro mammalian chromosome aberration test in Chinese Hamster Ovary cells. In an in vivo somatic mutation assay in Drosophila, negative results were obtained. In an in vivo Drosophila SLRL test and the Drosophila recessive lethal test, ambiguous results were obtained. An in vivo micronucleus assay and a combined chromosomal aberration and micronucleus assay indicated a negative result. Therefore, the available data indicate that fluoride does not interact directly with DNA and is not genotoxic when administered via an appropriate route (i. e. by oral or inhalation exposure). HFS acid is not predicted to be genotoxic. Toxicity for reproduction: No indication of reprotoxicity. Route of exposure: Inhalation and Dermal. Symptoms related to the physical, chemical and toxi cological characteristics: Corrosive to the eyes and skin. Chronic exposure may lead to dental or skeletal fluorosis. Section 12. Ecological Information 12.1 Toxicity Toxic to aquatic organisms.

Effect dose Species Method Remark Acute oral toxicity LD50 430 mg/kg bw. Rats n.a. Reliability of the study

could not be assessed and is therefore not deemed suitable for classification.


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12.2 Persistence and degradability Not considered to be persistent or biodegradable. The substance is inorganic and will hydrolyse and dissociate under environmental conditions to form fluoride and silicate ions. No biodegradation of the substance or these ions will occur. 12.3 Bioaccumulative potential The calculated BCF is between <2 and >58 L/kg wet weight, which is below the threshold of 2000, indicating Hexafluorosilicic acid does not satisfy the criterion for classification as bioaccumulative. 12.4 Mobility in soil Fluoride is the predominant ion in soil above pH of 6. Below pH 5.5, adsorption is low as fluoride exists as complexes. Above pH 5.5, adsorption is lower due to reduced electrostatic potential. The occurrence of precipitation of fluoride ions at higher concentrations reduces the concentration of free fluoride in calcareous soils. Fluoride is extremely immobile in soil as a result of precipitation and adsorption, with leaching of 5% observed in soil with fluoride concentrations up to 80mg/dm3. 12.5 Results of PBT and vPvB assessment This substance is not identified as a PBT substance 12.6 Other adverse effects No further details Section 13. Disposal Considerations 13.1 Waste treatment methods Disposal operations – Collect leaking and spilled liquid in sealable iron containers as far as possible. Absorb remaining liquid in sand or inert absorbent and remove to safe place. Disposal of packaging – No specific information provided. Please follow all local, regional, national and int ernational laws. Section 14. Transport Information 14.1 UN number 1778

Aquatic toxicity

Effect dose

Exposure time

Species Method Evaluation Remark

Acute fish toxicity

LC50 96 h Lepomis macrochirus

Screening study of acute fish toxicity

50 mg/L

Acute daphnia toxicity

EC50 96 h Daphnia magna No guideline stated 26 – 48 mg/L

Result based on concentration of the fluoride ion.

Acute algae toxicity

EC50 96 h various algae species

No guideline stated 43 mg/L Result based on biomass using sodium fluoride.

Chronic fish toxicity

NOEC 21 days Oncorhynchus mykiss

No guideline stated 4 mg/L Result based on mortality

Chronic daphnia toxicity

NOEC 21 days Daphnia magna No specific guideline stated.

3.7 mg/L Result based on reproductive effects observed following nominal concentration.


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14.2 UN proper shipping name Fluorosilicic acid 14.3 Transport hazard class(es) 8 14.4 Packing group II 14.5 Environmental hazards Environmentally Hazardous Substance 14.6 Special precautions for user No information available 14.7 Transport in bulk according to Annex II of MAR POL73/78 and the IBC Code Not applicable to packaged goods Section 15. Regulatory Information 15.1 Safety, health and environmental regulations/l egislation specific for the substance or mixture No further information 15.2 Chemical safety assessment A chemical safety assessment has been conducted. Section 16. Other Information Other information This safety data sheet is prepared in accordance with Regulation (EU) No 453/2010. * indicates text in the SDS which has changed since the last revision. Risk phrases used in Section 3 H314 Causes severe skin burns and eye damage. Note: The regulatory information given above only indicates the principal regulations specifically applicable to the product described in the safety data sheet. The user's attention is drawn to the possible existence of additional provisions which complete these regulations. Refer to all applicable national, international and local regulations or provisions.


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Annex to extended Safety Data Sheet (eSDS):

Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 1: Manufacture of HFS acid. 1

Exposure Scenario 1

Manufacturing of HFS acid Processes Covered: Environmental Releases ERC1: Manufacture of substances Worker Processes PROC01: Use in closed process, no likelihood of exposure. PROC02: Use in closed, continuous process with occasional controlled exposure. PROC03: Use in closed batch processes. PROC08a: Transfer of substance or preparation (charging/discharging) from/to vessels/large containers at non-dedicated facilities. PROC08b: Transfer of substance or preparation (charging/discharging) from/to vessels/large containers at dedicated facilities. PROC09: Transfer of formulations to small containers. PROC15: Laboratory use. Hexafluorosilicic Acid is a by-product from the reaction between Fluorapatitte and Sulphuric acid during Phosphoric acid production. The reaction produces Hydrogen fluoride, which in turn reacts with silicate contaminates in Fluorapatitte according to the following equation: SiO2 + 6 HF → H2SiF6 + 2 H2O The off-gas is released during phosphoric acid evaporation and concentration. It is absorbed in an absorption column with water. The final concentration of the Hexafluorosilicic Acid after the absorption step is 10 – 30%. The Hexafluorosilicic Acid flows in a closed loop in the system and is stored in closed tanks. The processes involved in the manufacture of Hexafluorosilicic Acid are variable in relation to enclosure. Some processes are fully enclosed while others are open. Some processes are continuous while others are batch processes. Some are indoors while others are outdoors. Due to the hazardous and corrosive nature of Hexafluorosilicic Acid the production systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to manufacture of HFS acid. Contributing Worker Scenarios: Worker exposure arising due to day to day use in closed processes with no likelihood of exposure, day to day use in closed continuous processes with occasional exposure (such as sampling), use in closed batch processes, transfer of substance to and from vessels and containers, transfer of formulations to small containers and laboratory use.


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2.1

Contributing scenario 1 controlling environmental exposure for ES 1

Environmental exposure arising due to manufacture of HFS acid.

Section 2.1 describes the environmental releases that may occur during the manufacture of HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions are monitored and controlled. Liquid wastes would generally be treated (neutralisation to neutral pH and/or precipitation) prior to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. Sludge from the waste water treatment plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics

HFS acid is a liquid at room temperature and pressure with a typical purity of around 95% (range 80 – 100%). It is a fuming liquid with a strong pungent odour. The vapour pressure of a 10 % aqueous solution of hexafluorosilicic acid is reported to be 2.30 kPa at 20 degrees Celsius. (REACH Centre, 2010). The vapour pressure of a 35% aqueous solution of hexafluorosilicic acid is reported to be 30 hPa at 20 degrees Celsius. However the reported vapour pressure is considered likely to be attributable to the release of hydrogen fluoride vapour (IPCS, 2004). HFS acid is miscible in water and decomposes upon heating. Amounts used

Production sites may manufacture up to a largest individual site value of 25,000 tonnes per annum, with approximately 80,000 tonnes produced per year in the EU. According to the guidance for this tonnage band, the default REACH number of emission days per year is 330. Frequency and duration of use

Frequency of use is estimated to be 220 days per year, with a standard 8 hour working day. Actual use of HFS Acid may be in continuous processes or batch processes Environmental factors influenced by risk management

Flow rate of receiving water at least 18,000 m3 per day. Dilution of STP emissions at least 10 fold.

Other operational conditions affecting environmental exposure

Production takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Manufacturing processes may be indoor or outdoor. Technical conditions and measures at process level (source) to prevent release

Manufacture is carried out indoors or outdoors in dedicated facilities and losses to surface water or the municipal STP should be prevented by on site WWTP removal. With regards to environmental emissions the loss of flouride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture flouride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from manufacturing or from the onsite WWTP should not exceed 3,760 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Organizational measures to prevent/limit releases from site

Workers are fully trained in order to prevent accidental release and measures in place during the handling of HFS ensure contact between HFS and adjacent air is reduced. Exposures may be monitored to ensure airborne concentrations are within acceptable levels. Conditions and measures related to municipal STP

Direct emissions to the municipal STP should not be made.

Conditions and measures related to external treatment of waste for disposal


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Residues may be sent to external waste treatment, on-site effluent treatment or recycled back into the manufacturing process. Sludge from the onsite WWTP should be recycled, incinerated or sent to landfill. Conditions and measures related to external recovery of waste

There is no envisaged external recovery of waste. Waste sludge is reduced and then incinerated or sent to landfill and emissions to air are not collected. 2.2

Contributing scenario 2 controlling worker exposure day to day use in closed processes with no likelihood of exposure.

Worker exposure arising due to day to day use in closed processes with no likelihood of exposure during the manufacturing process. Section 2.2 describes the potential exposure to workers during the manufacture of HFS acid from operation of closed systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. The potential exposure arises from the operation of the reactor and its associated machinery. Workers involved in production, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Production sites may manufacture up to a largest individual site value of 25,000 tonnes per annum, with approximately 80,000 tonnes produced per year in the EU. Production may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during manufacture is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management

Respiration volume under conditions of use: 10 m3/d Area of skin contact with the substance under conditions of use: 480cm2 (ECETOC default).


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Other given operational conditions affecting worker exposure

During the manufacture of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the manufacture or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the reactor or production vessels and the operation of the reactor vessel itself takes place under controlled conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker

Full system control should be in place during indoor operations when natural ventilation is not sufficient. Reactors and pipelines should be closed and sealed systems where possible. Organizational measures to prevent/limit release

Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are mostly not located in the breathing zone of workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc). All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.3

Contributing scenario 3 controlling worker exposure due to day to day use in closed continuous processes with occasional exposure (such as sampling)

Worker exposure arising due to day to day use in closed continuous processes with occasional exposure (such as sampling).

Section 2.3 describes the potential exposure to workers during the manufacture of HFS acid from operation of closed systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. The potential exposure arises from the operation of the reactor and its associated machinery. Workers involved in production, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required.


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Product characteristics



Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during manufacture is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management

Respiration volume under conditions of use: 10 m3/d Area of skin contact with the substance under conditions of use: 480cm2 (ECETOC default). Other given operational conditions affecting worker exposure


If this task is carried out indoors, the transfer of the substance from the reactor or production vessels and the operation of the reactor vessel itself takes place under controlled conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker



Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc). All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.


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2.4

Contributing scenario 4 controlling worker exposure for day to day use in batch or other processes with some potential for exposure (such as sampling, cleaning, maintenance)

Worker exposure arising due to day to day use in batch or other processes with some potential for exposure (such as sampling, cleaning, maintenance). Section 2.4 describes the potential exposure to workers during day to day use of formulation and distribution machinery, pipelines and storage vessels. Potential exposure may occur during the day to day use however it is more likely to occur during tasks associated with the batch or other processes such as sampling of solutions, cleaning and routine maintenance. Workers involved in production, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics



Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during manufacture is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, cleaning and maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management




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Contributing scenario 5 controlling worker exposure for transfer of produced HFS acid to and from large and vessels and containers

Worker exposure arising due to transfer of produced HFS acid to and from vessels and containers.

Section 2.5 describes the potential exposure to workers during the transfer of manufactured of HFS acid to and from large sized vessels and containers. The potential exposure arises from the transfer of the substance from the reactor to storage areas or vessels. Workers involved in this transfer of the substance will be exposed in the manual handling of the substance to storage vessels and potentially during the loading of road and rail tankers. Large tanks are generally bottom filled. Workers involved in transfer of materials to and from these large sized containers and vessels are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics

HFS acid is a liquid at room temperature and pressure with a typical purity of around 95% (range 80 – 100%). It is a fuming liquid with a strong pungent odour. The vapour pressure of a 10 % aqueous solution of hexafluorosilicic acid is reported to be 2.30 kPa at 20 degrees Celsius. (REACH Centre, 2010).


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The vapour pressure of a 35% aqueous solution of hexafluorosilicic acid is reported to be 30 hPa at 20 degrees Celsius. However the reported vapour pressure is considered likely to be attributable to the release of hydrogen fluoride vapour (IPCS, 2004). HFS acid is miscible in water and decomposes upon heating. Amounts used


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during manufacture is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management






Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of HFS acid to and from vessels and containers. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.6

Contributing scenario 6 controlling worker exposure for transfer to small containers

Worker exposure arising due to transfer to small containers in a dedicated filling line.

Section 2.6 describes the potential exposure to workers during the filling of small containers in dedicated filling lines. Potential exposure is most likely to occur during tasks associated with the actual filling of the containers themselves.


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Workers involved in transfer of materials to small containers in dedicated filling lines are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics









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Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved n the transfer of HFS acid to small containers in a dedicated filling line. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.7

Contributing scenario 7 controlling worker exposure for laboratory use

Worker exposure arising due to laboratory use of HFS acid (small scale non-industrial laboratories).

Section 2.10 describes the potential exposure to workers during laboratory use and production of HFS acid especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. Potential exposure is most likely to occur during tasks associated with the actual transfer or mixing of the HFS Acid solutions. Workers involved in laboratory based uses of HFS Acid are trained in the procedures of general safe use of chemicals and acids and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. A safety shower may also be located in the area of use encase of accidental spillage. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Amounts use in a non-industrial lab setting are likely to be small with less than 1 litre or 1 kilogram present on site.

Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Use of HFS acid is not likely to be this frequent in practice. Human factors not influence by risk management


During the use of HFS acid indoors in a laboratory environment, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during its use in the laboratory. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the use of HFS acid in a laboratory is generally conducted under controlled conditions.


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All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker



Workers may potentially be exposed to HFS acid when using it in a laboratory especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.

3

Exposure estimation and reference to its source

A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 1 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 1 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 1 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 1. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th

(worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 1 are shown in the tables below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP was considered during derivation of the values below. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1

PEC Values PEC in sewage effluent 7.3

PEC in aquatic compartment (mg/L): Freshwater Marine Water

0.77

0.07


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PEC in sediments (mg/kg): Freshwater sediments Marine water sediments

0.619

0.06

PEC in soil and groundwater: Agricultural soil (averaged over 30 days (in mg/kg)

Groundwater (in mg/L)

0.218 1.42

PEC in air: annual average (mg/M3) 0.944

The following RCR values were obtained:

Compartments PEC PNEC PEC/PNEC Discussion

Freshwater (Tier 2)

0.77 0.9 0.85 Safe use demonstrated in tier 2 with WWTP removal and precipitation.

Tier 2 Soil 0.218 11 0.019 Safe use demonstrated in tier 2 considering no spreading of sludge to soil.

Tier 2 STP 7.3 51 0.14 In the second tier assessment all waste acid is treated before any possible release to a municipal STP or any biological phase of an STP. As such there is no indicated risk.

Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with production and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes


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and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial production and use plants is adequately managed.

The following values were obtained using ART for worker exposure

Parameters and assumptions used in the ART model to conduct a Tier 2 assessment of inhalation exposure concentrations

Details PROC Parameters/ assumptions Exposure duration All 480 min Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction All Substantial (10-50%) Primary emission source proximity 1, 2, 3, 8a, 8b Primary emission source is not located in the breathing zone

of the worker - the assessment for this activity involves a primary far-field emission source only (workers are in a control room)

9, 15 Primary emission source is located in the breathing zone of the worker

Activity class All Transfer of liquid products Containment 1, 2, 3, 9 Handling reduces contact between product and adjacent air,

controlled loading 3, 9 Submerged loading 8a, 8b n/a due to bottom loading or tankers 15 Open process Localised controls 3 Vapour recovery systems; LEV 1, 2, 8a, 8b,

9, 15 LEV

Segregation 1, 2 Complete segregation of workers in separate control room 3, 8a, 8b Partial segregation of workers Fugative emission source 1, 8b, 9 Process fully enclosed – not openly breached for sampling 3, 8a, 15 Not fully enclosed – effective housekeeping practices in place. Dispersion 1, 2, 8a, 8b, 9 Outdoors not close to buildings 3 Outdoors close to buildings All Indoors, any sized room, only good natural ventilation

Acute/short-term and long-term inhalation exposure concentrations derived using the ART model


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Estimated Short-term Exposure Concentrations (mg/m3)

Estimated Long-term Exposure Concentration (mg/m3)

Contributing exposure scenario (CES)

PROC Physical state of material

50th percentile value




Indoor Contributing exposure scenario 2

1 Liquid 3.7 x10-01 1.2 4.5 x10-01 1

Contributing exposure scenario 3

2 Liquid 3.7 x10-01 1.2 4.5 x10-01 1


3 Liquid 2.2 x10-01 4.0 x10-01 2.7 x10-01 6.2 x10-01

8a Liquid 3.7 x10-01 1.2 4.4 x10-01 1 Contributing exposure scenario 5 8b Liquid 3.7 x10-01 1.2 4.5 x10-01 1


9 Liquid 4.4 x10-01 1.4 5.4 x10-01 1.2


15 Liquid 1.5 x10-01 4.6 x10-01 1.8 x10-01 4.1 x10-01

Outdoor Contributing exposure scenario 2

1 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


2 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


3 Liquid 7.2 x10-02 4.8 x10-01 1.7 x10-01 4 x10-01

8a Liquid 2.4 x10-03 1.6 x10-02 5.7 x10-03 1.4 x10-02 Contributing exposure scenario 5 8b Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


9 Liquid 7.2 x10-02 4.7 x10-01 1.7 x10-01 4 x10-01

Quantitative risk characterisation for workers

Inhalation exposure description

CES PROC Code ES 1- 90th exposure concentrations (mg/m3)

Leading toxic end point / Critical effect

DNEL (mg/m3)

Risk characterisation ratio

PROC 1 indoor

1.2 3.8 x10-01 CES 2

PROC 1 outdoor

1.6 x10-02

Respiratory irritation and corrositivity

3.125

5.1 x10-03

PROC 2 indoor

1.2 3.125 3.8 x 10-01 CES 3

PROC 2 outdoor

1.6 x 10-02

Respiratory irritation and corrositivity 5.1 x 10-03

PROC 3 indoor

4.0 x10-01 2.2 x10-01 CES 4

PROC 3 outdoor

4.8 x10-01


3.125

1.5 x10-01

PROC 8a indoor

1.2 3.8 x10-01

PROC 8a outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 8b indoor

1.2 3.8 x10-01

Acute effects

CES 5

PROC 8b outdoor

1.6 x10-02


3.125

5.1 x10-03


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PROC 9 indoor

1.4 4.5 x10-01 CES 6

PROC 9 outdoor

4.7 x10-01


3.125

1.5 x10-01

PROC 15 indoor

4.6 x10-01 1.5 x10-01 CES 7

PROC 15 outdoor

-


3.125

-

PROC 1 indoor

1 5.3 x10-01 CES 2

PROC 1 outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 2 indoor

1 5.3 x 10-03 CES 3

PROC 2 outdoor

1.4 x 10-02


1.88

7.4 x 10-03

PROC 3 indoor

6.2 x10-01 3.3 x10-01 CES 4

PROC 3 outdoor

4 x10-01


1.88

2.1 x10-01

PROC 8a indoor

1 5.3 x10-01

PROC 8a outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 8b indoor

1 5.3 x10-01

CES 5

PROC 8b outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 9 indoor

1.2 6.4 x10-01 CES 6

PROC 9 outdoor

4 x10-01


1.88

2.2 x10-01

PROC 15 indoor

4.1 x10-01 Respiratory irritation and corrositivity

1.88 2.2 x10-01

Long term effects

CES 7

PROC 15 outdoor

- -

4

Guidance to DU to evaluate whether he works inside the boundaries set by the ES

Environmental releases: In order to work within the boundaries of the ES the following conditions should be met:

• Local emission to air less than 3,760 kg per day • When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the waste-water stream should be reduced to 7.3 mg/L maximum using fluoride precipitation in the

WWTP • Residues may be sent to external waste treatment, on-site effluent treatment or recycled back into the manufacturing

process. • Measured emissions should be ensured to lead to concentrations in the environment which are less than the relevant

PNECs as listed in section 3 above Worker exposure:


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In order to work within the boundaries of the ES the following conditions should be met:

• Health monitoring should be conducted regularly to ascertain the potential levels of exposure. • Personal protective clothing (e.g. face/eye protection, helmet, gloves, boots and protective overalls) should be worn

when any potential contact may arise. • All technological devices should have a proper quality certification, and are regularly controlled and maintained to

avoid the uncontrolled discharge of HFS acid. • Workers should be fully trained. • Any measured worker exposure levels should be confirmed to be below the relevant DNEL as presented in section 3

above. •


Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 2: Distribution of HFS acid.

1

Exposure Scenario 2

Distribution of HFS Acid Processes Covered: Environmental Releases ERC2: Formulation of preparations Worker Processes PROC01: Use in closed process, no likelihood of exposure. PROC08b: Transfer of substance or preparation (charging/discharging) from/to vessels/large containers at dedicated facilities. PROC09: Transfer of formulations to small containers. PROC15: Laboratory use Manufactured HFS Acid is distributed widely to many industrial and municipality users. Liquid HFS Acid is transported to chemical formulation facilities which produce aqueous solutions of HFS Acid. Aqueous HFS Acid products are then distributed to a wide range of industrial end-users. Manufactured anhydrous liquid HFS Acid is stored and transported as a liquid by rail and road in specialised, authorised containers (e.g. tanks and tank trucks approved for transporting HFS Acid). HFS Acid is then used to produce aqueous HFS Acid solutions of various concentrations. Distributors of anhydrous and aqueous HFS Acid can operate on a regional or national level. Contributing Environmental Scenario: Environmental exposure arising due to distribution of HFS Acid. Contributing Worker Scenarios: Worker exposure arising due to day to day use in closed processes with no likelihood of exposure, transfer to small containers, transfer of substance to and from large vessels and containers and laboratory use.


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2.1


Environmental exposure arising due to distribution of HFS Acid.

Section 2.1 describes the environmental releases that may occur during the distribution of HFS Acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions are monitored and controlled. Liquid wastes would generally be treated (neutralisation to neutral pH and/or precipitation) prior to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. Sludge from the waste water treatment plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Distribution sites may use up to a largest individual site value of 10,000 tonnes per annum, with approximately 30,000 tonnes distributed per year in the EU. According to the guidance for this tonnage band, the default REACH number of emission days per year are 330. Frequency and duration of use




Distribution takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions; with transfer pipelines either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Distribution processes may be indoor or outdoor. Technical conditions and measures at process level (source) to prevent release

Distribution is carried out indoors or outdoors in dedicated facilities and losses to surface water or the municipal STP should be prevented by on site WWTP removal. With regards to environmental emissions the loss of flouride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture flouride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from manufacturing or from the onsite WWTP should not exceed 750 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Organizational measures to prevent/limit releases from site

Workers are fully trained in order to prevent accidental release and exposures may be monitored to ensure airborne concentrations are within acceptable levels. Conditions and measures related to municipal STP



Residues may be sent to external waste treatment, on-site effluent treatment or recycled back into the manufacturing process. Sludge from the onsite WWTP should be recycled, incinerated or sent to landfill.


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Conditions and measures related to external recovery of waste



Worker exposure arising due to day to day use in closed processes with no likelihood of exposure during the distribution processes. Section 2.2 describes the potential exposure to workers during the distribution of HFS Acid during operation of closed systems. The potential exposure arises from the operation of transfer/distribution equipment and its associated machinery. Workers involved in distribution of HFS Acid are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Distribution sites may use up to a largest individual site value of 10,000 tonnes per annum, with approximately 30,000 tonnes distributed per year in the EU. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during distribution is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the distribution of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal


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protective equipment is also used to prevent the potential for dermal exposure during the distribution or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the reactor or distribution vessels and the operation of the distribution equipment itself takes place under controlled conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker


Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are mostly not located in the breathing zone of the worker. Conditions and measures related to personal protection, hygiene and health.


Contributing scenario 3 controlling worker exposure for transfer of produced HFS acid to and from large and vessels and containers at dedicated facilities

Worker exposure arising due to transfer of produced HFS acid to and from vessels and containers at dedicated facilities.

Section 2.5 describes the potential exposure to workers during the transfer of distribution of HFS acid to and from large sized vessels and containers. The potential exposure arises from the transfer of the substance from the reactor to storage areas or vessels. Workers involved in this transfer of the substance will be exposed in the manual handling of the substance to storage vessels and potentially during the loading of road and rail tankers. Large tanks are generally bottom filled. Workers involved in transfer of materials to and from these large sized containers and vessels are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


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Distribution sites may distribute up to a largest individual site value of 10,000 tonnes per annum, with approximately 30,000 tonnes distributed per year in the EU. Use may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during distribution is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the distribution of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the distribution or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release




Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of produced HFS acid to and from vessels and containers at dedicated facilities. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.


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2.4



Section 2.4 describes the potential exposure to workers during the filling of small containers in dedicated filling lines. Potential exposure is most likely to occur during tasks associated with the actual filling of the containers themselves. Workers involved in transfer of materials to small containers in dedicated filling lines trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Distribution sites may distribute up to a largest individual site value of 10,000 tonnes per annum, with approximately 30,000 tonnes distributed per year in the EU. Use may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during distribution is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the distribution of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the distribution or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the reactor or distribution vessels and the operation of the distribution equipment itself takes place under controlled conditions.


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Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of HFS acid to small containers in a dedicated filling line. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.5


Worker exposure arising due to laboratory use of HFS Acid (small scale non-industrial laboratories).

Section 2.5 describes the potential exposure to workers during laboratory use and distribution of HFS acid especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. Potential exposure is most likely to occur during tasks associated with the actual transfer or mixing of the HFS Acid solutions. Workers involved in laboratory based uses of HFS Acid are trained in the procedures of general safe use of chemicals and acids and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics




Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Again use of HFS acid is not likely to be this frequent in practice. Human factors not influence by risk management

Respiration volume under conditions of use: 10 m3/d Area of skin contact with the substance under conditions of use: 480cm2 (ECETOC default).


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Other given operational conditions affecting worker exposure

During the use of HFS acid indoors in laboratories, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the distribution or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release




Workers may potentially be exposed to HFS acid through its use in laboratory environments especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 2 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 2. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 2 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 2 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 2. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 2 are shown below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP was considered during derivation of the values below. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


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PEC Values PEC in sewage effluent 7.3


0.735

0.066 PEC in sediments (mg/kg): Freshwater sediments Marine water sediments

0.591

0.059

PEC in soil and groundwater: Agricultural soil (averaged over 30 days (in mg/kg)


0.045 0.293

PEC in air: annual average (mg/M3) 0.189



Freshwater (Tier 2)

0.735

0.9 0.816 Safe use demonstrated in

tier 2 with WWTP removal and precipitation.

Tier 2 Soil 0.045 11 0.004 Safe use demonstrated in tier 2 considering no spreading of sludge to soil.

Tier 2 STP 7.3 51 0.14 In the second tier assessment all waste acid is treated before any possible release to a municipal STP or any biological phase of an STP. As such there is no indicated risk.

Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with distribution and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and


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control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should also be located in the areas of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial distribution and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration All 480 min Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction All Substantial (10-50%) Primary emission source proximity 1, 8b Primary emission source is not located in the breathing zone


9, 15 Primary emission source is located in the breathing zone of the worker

Activity class All Transfer of liquid products Containment 1, 9 Handling reduces contact between product and adjacent air,

controlled loading 9 Submerged loading 8b n/a due to bottom loading or tankers 15 Open process Localised controls 1, 8b, 9, 15 LEV Segregation 1 Complete segregation of workers in separate control room 8b Partial segregation of workers Fugative emission source 1, 8b, 9 Process fully enclosed – not openly breached for sampling


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15 Not fully enclosed – effective housekeeping practices in place. Dispersion 1, 8b, 9 Outdoors not close to buildings 1, 8b, 9, 15 Indoors, any sized room, only good natural ventilation











1 Liquid 3.7 x10-01 1.2 4.5 x10-01 1


8b Liquid 3.7 x10-01 1.2 4.5 x10-01 1


9 Liquid 4.4 x10-01 1.4 5.4 x10-01 1.2


15 Liquid 1.5 x10-01 4.6 x10-01 1.8 x10-01 4.1 x10-01


1 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


8b Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


9 Liquid 7.2 x10-02 4.7 x10-01 1.7 x10-01 4 x10-01


Inhalation effects description



DNEL (mg/m3)


PROC 1 indoor

1.2 3.8 x10-01 CES 2

PROC 1 outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 8b indoor

1.2 3.8 x10-01 CES 3

PROC 8b outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 9 indoor

1.4 4.5 x10-01 CES 4

PROC 9 outdoor

4.7 x10-01


3.125

1.5 x10-01

PROC 15 indoor

4.6 x10-01 1.5 x10-01

Acute effects

CES 5

PROC 15 outdoor

-


3.125

-

PROC 1 indoor

1 5.3 x10-01 CES 2

PROC 1 outdoor

1.4 x10-02


1.88

7.4 x10-03

Long term effects

CES 3 PROC 8b indoor

1 Respiratory irritation and

1.88 5.3 x10-01


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PROC 8b outdoor

1.4 x10-02 corrositivity 7.4 x10-03

PROC 9 indoor

1.2 6.4 x10-01 CES 4

PROC 9 outdoor

4 x10-01


1.88

2.2 x10-01

PROC 15 indoor

4.1 x10-01 2.2 x10-01 CES 5

PROC 15 outdoor

-


1.88

-

4



• Local emission to air less than 750 kg per day • When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the waste-water stream should be reduced to 7.3 mg/L maximum using fluoride precipitation in the



PNECs as listed in section 3 above

Worker exposure: In order to work within the boundaries of the ES the following conditions should be met:




above.


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Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 3: Industrial formulation of HFS acid.

1

Exposure Scenario 3

Industrial formulation of HFS Acid Processes Covered: Environmental Releases ERC2: Industrial formulation of preparations ERC 6a: Industrial use of intermediates Worker Processes PROC03: Use in closed batch processes PROC04: Use in batch and other processes where the potential for exposure occurs PROC05: Mixing or blending in batch processes for formulation of preparations and articles (multistage and/or significant contact) PROC09: Transfer of industrial formulations to small containers. PROC15: Laboratory use Manufactured HFS Acid is formulated widely at many industrial and municipality users. Liquid HFS Acid is transported to chemical industrial formulation facilities which produce aqueous solutions of HFS Acid and various formulations. Aqueous HFS Acid products are then formulated to a wide range of industrial end-users. Manufactured anhydrous liquid HFS Acid is stored and transported as a liquid by rail and road in specialised, authorised containers (e.g. tanks and tank trucks approved for transporting HFS Acid). HFS Acid is then used to produce aqueous HFS Acid solutions of various concentrations. Contributing Environmental Scenario: Environmental exposure arising due to industrial formulation of HFS Acid. Contributing Worker Scenarios: Worker exposure arising due to day to day use in batch processes, transfer to small containers, mixing and blending and laboratory use. 2.1


Environmental exposure arising due to industrial formulation of HFS Acid.

Section 2.1 describes the environmental releases that may occur during the industrial formulation of HFS Acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions are monitored and controlled. Liquid wastes would generally be treated (neutralisation to neutral pH and/or precipitation) prior to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. Sludge from the waste water treatment plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading.


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Industrial formulation sites may use up to a largest individual site value of 20,000 tonnes per annum, with approximately 25,000 tonnes formulated per year in the EU. According to the guidance for this tonnage band, the default REACH number of emission days per year are 330. Frequency and duration of use




Industrial formulation takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Manufacturing processes may be indoor or outdoor. Technical conditions and measures at process level (source) to prevent release

Manufacture is carried out indoors or outdoors in dedicated facilities and losses to surface water or the municipal STP should be prevented by on site WWTP removal. With regards to environmental emissions the loss of flouride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture flouride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from manufacturing or from the onsite WWTP should not exceed 3030 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Organizational measures to prevent/limit releases from site






Contributing scenario 2 controlling worker exposure for formulation use in batch processes.

Worker exposure arising due to formulation use in batch processes.

Section 2.2 describes the potential exposure to workers during the industrial formulation of HFS Acid during operation of closed batch systems and batch systems where there is some potential for exposure. The potential exposure arises from the operation of transfer/industrial formulation equipment and its associated machinery.


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Workers involved in industrial formulation of HFS Acid are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Industrial formulation sites may use up to a largest individual site value of 20,000 tonnes per annum, with approximately 25,000 tonnes formulated per year in the EU. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during industrial formulation is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the industrial formulation of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the industrial formulation or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the reactor or industrial formulation vessels and the operation of the industrial formulation equipment itself takes place under controlled conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker

Full system control should be in place during indoor operations when natural ventilation is not sufficient. Reactors and


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pipelines should be closed and sealed systems where possible.

Organizational measures to prevent/limit release

Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located within the breathing zone of workers. Conditions and measures related to personal protection, hygiene and health.


Contributing scenario 3 controlling worker exposure for mixing and blending of HFS Acid

Worker exposure arising due to mixing or blending of HFS acid in batch processes for formulation of preparations and articles (multistage and/or significant contact) Section 2.5 describes the potential exposure to workers during the mixing and blending of HFS acid. . Workers involved in the mixing and blending of the substance will be exposed in the manual handling of the substance to and potentially during the mixing and blending of the substance.. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Industrial formulation sites may distribute up to a largest individual site value of 20,000 tonnes per annum, with approximately 25,000 tonnes formulated per year in the EU. Use may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during industrial formulation is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


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Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Frequent monitoring for health effects is conducted by medical surveillance programs. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. mixing equipment, valves, pumps or tanks etc). All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.4



Section 2.4 describes the potential exposure to workers during the filling of small containers in dedicated filling lines. Potential exposure is most likely to occur during tasks associated with the actual filling of the containers themselves. Workers involved in transfer of materials to small containers in dedicated filling lines are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required.


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Industrial formulation sites may distribute up to a largest individual site value of 20,000 tonnes per annum, with approximately 25,000 tonnes formulated per year in the EU. Use may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during industrial formulation is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management





Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of HFS acid to small containers in a dedicated filling line. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety


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shower is required nearby in case of accidental spillage. 2.5


Worker exposure arising due to laboratory use of HFS acid (small scale non-industrial laboratories).

Section 2.5 describes the potential exposure to workers during laboratory use and industrial formulation of HFS acid especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. Potential exposure is most likely to occur during tasks associated with the actual transfer or mixing of the HFS Acid solutions. Workers involved in laboratory based uses of HFS Acid are trained in the procedures of general safe use of chemicals and acids and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics




Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Again use of HFS acid is not likely to be this frequent in practice. Human factors not influence by risk management


During the use of HFS acid indoors in a laboratory environment, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the industrial formulation or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release




Workers may potentially be exposed to HFS acid when used in a laboratory, especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. All operations are performed in a


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controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 3 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 3. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 3 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 3 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 3. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 3 are shown below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP was considered during derivation of the values below. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1

PEC Values PEC in sewage effluent ERC 2 and 6a: 7.3


ERC 2: 0.734

ERC 6a: 0.734

ERC 2: 0.07

ERC 6a: 0.07

PEC in sediments (mg/kg): Freshwater sediments Marine water sediments

ERC 2 0: 0.59

ERC 6a: 0.59

ERC 2; 0.059

ERC 6a: 0.059


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PEC in soil and groundwater:

Agricultural soil (averaged over 30 days (in mg/kg)


ERC 2: 0.327

ERC 6a: 0.415 ERC 2: 1.13

ERC 6a: 1.13

PEC in air: annual average (mg/M3) ERC 2: 0.381

ERC 6a: 0.762



Freshwater (Tier 2)

ERC 2: 0.734

ERC 6a: 0.734

0.9 ERC 2: 0.81

ERC 6a: 0.81

Safe use demonstrated in tier 2 with WWTP removal and precipitation.

Tier 2 Soil ERC 2: 0.327

ERC 6a: 0.415

11 ERC 2 0.029

ERC 6a 0.037

Safe use demonstrated in tier 2 considering no spreading of sludge to soil.

Tier 2 STP 7.3

51 0.143

In the second tier assessment all waste acid is treated before any possible release to a municipal STP or any biological phase of an STP. As such there is no indicated risk.

Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with industrial formulation and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes


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and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should also be located in the areas of use in case of accidental spillage.The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial formulation and use in plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration All 480 min Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction All Substantial (10-50%) Primary emission source proximity 3, 5 Primary emission source is not located in the breathing zone


4, 9, 15 Primary emission source is located in the breathing zone of the worker

Activity class 3, 4, 9, 15 Transfer of liquid products 5 Activities with open liquid surfaces -activities with agitated

surfaces Containment 3, 9 Handling reduces contact between product and adjacent air,

controlled loading 3, 4, 9 Submerged loading 4, 15 Open process Localised controls 3, 4, 5 Vapour recovery systems; LEV 9, 15 LEV Segregation 3 Partial segregation of workers Fugative emission source 9 Process fully enclosed – not openly breached for sampling 3, 4, 15, 5 Not fully enclosed – effective housekeeping practices in place. Dispersion 9 Outdoors not close to buildings 3, 4, 5 Outdoors close to buildings 3, 4, 9, 15, 5 Indoors, any sized room, only good natural ventilation



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Indoor 3 Liquid 2.2 x10-01 4.0 x10-01 2.7 x10-01 6.2 x10-01 Contributing exposure

scenario 2 4 Liquid 3.0 x10-01 9.2 x10-01 3.6 x10-01 8.2 x10-01 Contributing exposure scenario 3

5 Liquid 2.2 x10-01 6.9 x10-01 2.7 x10-01 6.2 x10-01


9 Liquid 4.4 x10-01 1.4 5.4 x10-01 1.2


15 Liquid 1.5 x10-01 4.6 x10-01 1.8 x10-01 4.1 x10-01

Outdoor 3 Liquid 7.2 x10-02 4.8 x10-01 1.7 x10-01 4 x10-01 Contributing exposure

scenario 2 4 Liquid 5.3 x10-02 3.5 x10-01 1.3 x10-01 3.0 x10-01 Contributing exposure scenario 3

5 Liquid 2.4 x10-02 1.6 x10-01 5.8 x10-02 1.4 x10-01


9 Liquid 7.2 x10-02 4.7 x10-01 1.7 x10-01 4 x10-01


Inhalation effects description



DNEL (mg/m3)


PROC 3 indoor

4.0 x10-01 2.2 x10-01

PROC 3 outdoor

4.8 x10-01


3.125

1.5 x10-01

PROC 4 indoor

9.2 x10-01 2.9 x10-01

CES 2

PROC 4 outdoor

3.5 x10-01


3.125

1.1 x10-01

PROC 5 indoor

6.9 x 10-01 2.2 x 10-01 CES 3

PROC 5 outdoor

1.6 x 10-01


3.125

5.2 x 10-02

PROC 9 indoor

1.4 4.5 x10-01 CES 4

PROC 9 outdoor

4.7 x10-01


3.125

1.5 x10-01

PROC 15 indoor

4.6 x10-01 1.5 x10-01

Acute effects

CES 5

PROC 15 outdoor

-


3.125

-

PROC 3 indoor

6.2 x10-01 3.3 x10-01

PROC 3 outdoor

4 x10-01


1.88

2.1 x10-01

PROC 4 indoor

8.2 x10-01 4.4 x10-01

Long term effects

CES 2

PROC 4 outdoor

3.0 x10-01


1.88

1.6 x10-01


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PROC 5 indoor

6.2 x 10-01 3.3 x 10-01 CES 3

PROC 5 outdoor

1.4 x 10-01


1.88

7.4 x 10-02

PROC 9 indoor

1.2 6.4 x10-01 CES 4

PROC 9 outdoor

4 x10-01


1.88

2.2 x10-01

PROC 15 indoor

4.1 x10-01 2.2 x10-01 CES 5

PROC 15 outdoor

-


1.88

-

4






PNECs as listed in section 3 above Worker exposure: In order to work within the boundaries of the ES the following conditions should be met:




above.


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Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 4: Use of HFS Acid as a water treatment chemical. 1

Exposure Scenario 4

Water treatment use of HFS acid Processes Covered: Environmental Releases ERC6b: Industrial use of reactive processing aids ERC8a: Wide dispersive indoor use of processing aids in open systems ERC8b: Wide dispersive indoor use of reactive substances in open systems Worker Processes PROC01: Use in closed process, no likelihood of exposure. PROC02: Use in closed, continuous process with occasional controlled exposure. PROC03: Use in closed batch processes. PROC08b: Transfer of substance or preparation (charging/discharging) from/to vessels/large containers at dedicated Drinking water is treated with Hexafluorosilicic Acid for the purpose of fluoridation. The processes involved in the handling of Hexafluorosilicic Acid are variable in relation to enclosure. Some processes are fully enclosed while others are open. Some processes are continuous while others are batch processes. Some are indoors while others are outdoors. This is a wide dispersive use and environmental emissions of Hexafluorosilicic Acid in treated water are extremely limited (almost no emissions). Given that upon contact with water Hexafluorosilicic Acid converts to ions and is fully miscible in and the fact that it is added in very small amounts the estimated concentrations in the environment as calculated in EUSES below are to be considered conservative. Due to the hazardous and corrosive nature of Hexafluorosilicic acid trioxide the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to water treatment of HFS acid. Contributing Worker Scenarios: Worker exposure arising due to day to day use in closed processes with no likelihood of exposure, day to day use in closed continuous processes with occasional exposure (such as sampling), use in closed batch processes and transfer of substance to and from vessels and containers. 2.1


Environmental exposure arising due to water treatment use of HFS acid.

Section 2.1 describes the environmental releases that may occur during the water treatment use of HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions from industrial sources are monitored and controlled. Liquid wastes from industrial sites would generally be treated prior to emission to


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remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to a maximum of 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. For water treatment use the values in the STP effluent may be below this due to the small on-site tonnages however any emissions should not exceed this value as a general rule. Sludge from the waste water treatment plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Water treatment sites may water treatment use up to a largest individual site value of 5,000 tonnes per annum as a worst case assumption. According to the guidance for this tonnage band, the default REACH number of emission days per year is 330. The number of emission days for wide dispersive uses is 365. Frequency and duration of use

Frequency of use is estimated to be 220 days per year, with a standard 8 hour working day.

Environmental factors influenced by risk management



Water treatment takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Technical conditions and measures at process level (source) to prevent release

Water treatment use is carried out indoors or outdoors in dedicated facilities and direct losses to surface water or the municipal STP should be prevented. With regards to environmental emissions the loss of flouride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture flouride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Industrial waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from water treatment use or from the onsite WWTP should not exceed 3,760 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Waste water from wide dispersive uses does not need to be treated. Organizational measures to prevent/limit releases from site


Direct emissions to the municipal STP should not be made for industrial treatment sites.


Residues may be sent to external waste treatment, on-site effluent treatment or recycled back into the industrial process. Sludge from the onsite industrial WWTP should be recycled, incinerated or sent to landfill. Conditions and measures related to external recovery of waste

There is no envisaged external recovery of waste. Waste industrial WWTP sludge is reduced and then incinerated or sent to landfill and emissions to air are not collected. 2.2



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Worker exposure arising due to day to day use in closed processes with no likelihood of exposure during the water treatment use process. Section 2.2 describes the potential exposure to workers during the water treatment use of HFS acid from operation of closed systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. Workers involved in water treatment, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Water treatment sites may water treatment use up to a largest individual site value of 5,000 tonnes per annum. Water treatment may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during water treatment use is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the water treatment use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the water treatment use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the storage vessels and operation of the water treatment equipment takes place under controlled conditions whenever possible. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker



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Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of workers. Conditions and measures related to personal protection, hygiene and health.


Contributing scenario 3 controlling worker exposure due to day to day use in closed continuous processes with occasional exposure (such as sampling)

Worker exposure arising due to day to day use in closed continuous processes with occasional exposure (such as sampling).

Section 2.3 describes the potential exposure to workers during the water treatment use of HFS acid from operation of closed systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. The potential exposure arises from the operation of the reactor and its associated machinery. Workers involved in water treatment, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Water treatment sites may water treatment use up to a largest individual site value of 5,000 tonnes per annum.


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during water treatment use is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, maintenance and cleaning are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place.


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Human factors not influence by risk management





Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Frequent monitoring for health effects is conducted by medical surveillance programs. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) ) involved in the sampling, cleaning and maintenance of the reactors and vessels. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.

2.4

Contributing scenario 4 controlling worker exposure for day to day use in batch processes

Worker exposure arising due to day to day use in batch or other processes with only limited potential for exposure (such as sampling, cleaning, maintenance). Section 2.4 describes the potential exposure to workers during day to day use of HFS Acid for water treatment in batch processes. Potential exposure may occur during the day to day use however it is more likely to occur during tasks associated with the batch or other processes such as sampling of solutions, cleaning and routine maintenance. Workers involved in water treatment, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


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Water treatment sites may water treatment use up to a largest individual site value of 5,000 tonnes per annum.


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during water treatment use is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, cleaning and routine maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management





Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Primary emission zones are not located in the breathing zones of workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the sampling, cleaning and routine maintenance of the reactors and vessels. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.


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2.5



Section 2.5 describes the potential exposure to workers during the transfer of HFS acid to and from large sized vessels and containers. The potential exposure arises from the transfer of the substance from the storage areas or vessels. Workers involved in this transfer of the substance will be exposed in the manual handling of the substance to storage vessels and potentially during the loading of road and rail tankers. Large tanks are generally bottom filled. Workers involved in transfer of materials to and from these large sized containers and vessels during water treatment are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Water treatment sites may water treatment use up to a largest individual site value of 5,000 tonnes per annum. Water treatment may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during water treatment use is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management



If being carried out indoors the transfer of the substance from the storage vessels and operation of the water treatment equipment takes place under controlled conditions whenever possible.


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Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zones of workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of produced HFS acid to and from vessels and containers at dedicated facilities. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.

3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 4 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 4. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 4 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 4 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 4. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 4 are shown in the tables below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP could be considered during derivation of the values below of industrial use scenarios for large tonnage sites however this was not formally required for the relatively small tonnages associated with water treatment use. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1

ERC Compartments Concentration (mg/L)

6b Effluent (in mg/L) 2

ERC Compartments Concentration aquatic


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(mg/L) Freshwater (in mg/L) 0.241

8a Marine water (in mg/L) 0.024

Freshwater (in mg/L) 0.0048 8b Marine water (in mg/L) 0.0003


ERC Compartments Concentration

Freshwater sediment (in mg/kg)

0.194 8a

Marine sediment (in mg/kg)

0.016


0.003 8b


0.0003


0.177 6b


0.017

ERC Compartments PEC (local)


1.64 6b

Groundwater (in mg/L) 3.48

ERC Local concentration

PEC air (local+regional)

6b Annual average PEC in air, total (mg/m3)

0.0788 0.0788


ERC Compartment PEC mg/L

PNEC mg/L

PEC/PNEC Comments

6b Tier 2 Freshwater 0.221 0.9 0.245 Safe use demonstrated in tier 2

8a Tier 1 Freshwater 0.241 0.9 0.267 Safe use demonstrated in tier 1

8b Tier 1 Freshwater 0.0048 0.9 0.053 Safe use demonstrated in


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tier 1


PNEC mg/kg

PEC/PNEC Comments

6b Soil 1.64 11 0.14 Safe use demonstrated in tier 2


PNEC mg/kg

PEC/PNEC Comments


Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with water treatment and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be


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working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. A safety shower is also located in the area of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial water treatment and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration All 480 min Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction All Substantial (10-50%) Primary emission source proximity 1, 2, 3, 8b Primary emission source is not located in the breathing zone


Activity class All Transfer of liquid products Containment 1, 2, 3 Handling reduces contact between product and adjacent air,

controlled loading 3, 9 Submerged loading 8b n/a due to bottom loading or tankers Localised controls 3 Vapour recovery systems; LEV 1, 2, , 8b LEV Segregation 1, 2 Complete segregation of workers in separate control room 3,8b Partial segregation of workers Fugative emission source 1, 8b Process fully enclosed – not openly breached for sampling 3 Not fully enclosed – effective housekeeping practices in place. Dispersion 1, 2, 8b, Outdoors not close to buildings 3 Outdoors close to buildings All Indoors, any sized room, only good natural ventilation











1 Liquid 3.7 x10-01 1.2 4.5 x10-01 1


2 Liquid 3.7 x10-01 1.2 4.5 x10-01 1


3 Liquid 2.2 x10-01 4.0 x10-01 2.7 x10-01 6.2 x10-01


8b Liquid 3.7 x10-01 1.2 4.5 x10-01 1


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1 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


2 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02


3 Liquid 7.2 x10-02 4.8 x10-01 1.7 x10-01 4 x10-01


8b Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02





DNEL (mg/m3)


PROC 1 indoor

1.2 3.8 x10-01 CES 2

PROC 1 outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 2 indoor

1.2 3.125 3.8 x 10-01 CES 3

PROC 2 outdoor

1.6 x 10-02


PROC 3 indoor

4.0 x10-01 2.2 x10-01 CES 4

PROC 3 outdoor

4.8 x10-01


3.125

1.5 x10-01

PROC 8b indoor

1.2 3.8 x10-01

Acute effects

CES 5

PROC 8b outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 1 indoor

1 5.3 x10-01 CES 2

PROC 1 outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 2 indoor

1 5.3 x 10-01 CES 3

PROC 2 outdoor

1.4 x 10-02


1.88

7.4 x 10-03

PROC 3 indoor

6.2 x10-01 3.3 x10-01 CES 4

PROC 3 outdoor

4 x10-01


1.88

2.1 x10-01

PROC 8b indoor

1 5.3 x10-01

Long term effects

CES 5

PROC 8b outdoor

1.4 x10-02


1.88

7.4 x10-03

4




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• Local emission to air less than 3,760 kg per day for an industrial site. Regional emissions should not exceed 13,700

kg per day in total. • When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the industrial waste-water stream should be reduced to 7.3 mg/L maximum using fluoride

precipitation in the WWTP. Actual emissions for this use may be below this level but this value should not be exceeded in any case.

• Residues may be sent to external waste treatment or on-site effluent treatment • Measured emissions should be ensured to lead to concentrations in the environment which are less than the relevant





above.


Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 5: Use of HFS Acid as a metal treatment chemical.

1

Exposure Scenario 5

Metal treatment use of HFS acid Processes Covered: Environmental Releases ERC6a: Industrial use resulting in manufacture of another substance (use of intermediates). Worker Processes PROC13: Treatment of articles by dipping and pouring Metal is treated with Hexafluorosilicic Acid by dipping and pouring processes. The processes involved in the handling of Hexafluorosilicic Acid are variable in relation to enclosure. Some processes are fully enclosed while others are open. Some processes are continuous while others are batch processes. Some are indoors while others are outdoors. This is a wide dispersive use and environmental emissions of Hexafluorosilicic Acid in treated water are extremely limited (almost no emissions). Given that upon contact with water Hexafluorosilicic Acid converts to ions and is fully miscible in and the fact that it is added in very small amounts the estimated concentrations in the environment as calculated in EUSES


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below are to be considered conservative. Due to the hazardous and corrosive nature of Hexafluorosilicic acid trioxide the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to metal treatment use of HFS acid. Contributing Worker Scenarios: Worker exposure arising due to treatment of metal articles by dipping and pouring. 2.1


Environmental exposure arising due to metal treatment use of HFS acid.

Section 2.1 describes the environmental releases that may occur during the metal treatment use of HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions from industrial sources are monitored and controlled. Liquid wastes from industrial sites would generally be treated prior to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to a maximum of 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. For metal treatment use the values in the STP effluent may be below this due to the small on-site tonnages however any emissions should not exceed this value as a general rule. It is expected that removal in the WWTP will be at least 90%. Sludge from the industrial waste treatment plant is sent for recovery (of metals), incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Metal treatment sites may use up to a largest individual site value of 788 tonnes per annum as a worst case assumption. The regional tonnage is around 1,000 tonnes. Frequency and duration of use

Frequency of use is estimated to be 220 days per year, with a standard 8 hour working day. 330 emission days is the REACH default number of days use expected per year. Environmental factors influenced by risk management



Metal treatment takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Technical conditions and measures at process level (source) to prevent release

Metal treatment use is carried out indoors or outdoors in dedicated facilities and direct losses to surface water or the municipal STP should be prevented. With regards to environmental emissions the loss of fluoride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture fluoride will be formed.


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Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Industrial waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from metal treatment use or from the onsite WWTP should not exceed 131 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Waste water from wide dispersive uses does not need to be treated. Organizational measures to prevent/limit releases from site






Contributing scenario 2 controlling worker exposure for treatment of articles by dipping and pouring

Worker exposure arising due to treatment of articles by dipping and pouring

Section 2.2 describes the potential exposure to workers during the metal treatment use of HFS acid from treatment of metal articles by dipping and pouring. Workers involved in metal treatment, handling, sampling and transfer of materials are trained in the procedures and use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Metal treatment sites may use up to a largest individual site value of 788 tonnes per annum. Metal treatment may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during metal treatment use is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place.


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Human factors not influence by risk management


During the metal treatment use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the metal treatment use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the storage vessels and operation of the metal treatment equipment takes place under controlled conditions whenever possible. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker

Full system control should be in place during indoor operations when natural ventilation is not sufficient. Treatment tanks, equipment and pipelines should be closed and sealed systems where possible. Organizational measures to prevent/limit release


Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the metal treatment use of HFS acid from treatment of metal articles by dipping and pouring. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 5 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 5. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 5 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 5 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 5. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 5 are shown in the tables below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP could be considered during derivation of the values below of industrial use scenarios for large tonnage sites however this was not formally required for the relatively small tonnages associated with metal treatment use.


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Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


6a Effluent (in mg/L) 2.52

Freshwater (in mg/L) 0.252 6a

Marine water (in mg/L) 0.0252


0.0079 6a


6a Annual average PEC in air, total (mg/m3)

0.015



PNEC mg/L

PEC/PNEC Comments



PNEC mg/kg

PEC/PNEC Comments

6a Tier 2 Soil 0.0079 11 0.0007 Safe use demonstrated in tier 2


PNEC mg/kg

PEC/PNEC Comments

6a Tier 2 STP 2.52 51 0.049 Based on worst possible downstream exposure of the STP

Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with metal treatment and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control


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this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should also be located in the areas of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial metal treatment and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration 13 480 min Product type 13 Liquid Process temperature 13 Room temperature (15-25oC) Vapour pressure 13 2300 pa Liquid weight fraction 13 Substantial (10-50%) Primary emission source proximity 13 Primary emission source is not located in the breathing zone


Activity class 13 Activities with open liquid surfaces -activities with undisturbed surfaces

Localised controls 13 Vapour recovery systems; LEV Segregation 13 Complete segregation of workers in separate control room


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Fugative emission source 13 Process fully enclosed – not openly breached for sampling Dispersion 13 Outdoors not close to buildings 13 Indoors, any sized room, only good natural ventilation










Indoor CES2 13 Liquid 8.0 x10-03 5.3 x10-02 1.9 x10-02 4.5 x10-02 Outdoor CES2 13 Liquid 2.5 x10-01 7.7 x10-01 3.0 x10-01 6.9 x10-01


Exposure details



DNEL (mg/m3)


PROC 13 indoor

5.3 x10-02 2.5 x10-01 Acute effects CES 2

PROC 13 outdoor

7.7 x10-01


3.125

1.7 x10-02

PROC 13 indoor

4.5 x10-02 3.7 x10-01 Long term effects

CES 2

PROC 13 outdoor

6.9 x10-01


1.88

2.4 x10-02

4



• Local emission to air less than 131 kg per day for an industrial site. • When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the industrial waste-water stream should be reduced to 7.3 mg/L maximum using fluoride

precipitation in the WWTP. Actual emissions for this use may be below this level but this value should not be exceeded in any case. Removal in the WWTP should be at least 90%.



• Health monitoring should be conducted regularly to ascertain the potential levels of exposure.


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• Personal protective clothing (e.g. face/eye protection, helmet, gloves, boots and protective overalls) should be worn when any potential contact may arise.

• All technological devices should have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid.

• Workers should be fully trained. • Any measured worker exposure levels should be confirmed to be below the relevant DNEL as presented in section 3

above.


Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 6: Use of HFS Acid during the manufacture of metals. 1

Exposure Scenario 6

Metal manufacturing use of HFS acid Processes Covered: Environmental Releases ERC6a: Industrial use resulting in manufacture of another substance (use of intermediates) Worker Processes PROC01: Use in closed process, no likelihood of exposure. PROC03: Use in closed batch processes. PROC27b: Production of metals powders by wet methods. Hexafluorosilicic Acid is used during the manufacture of metals and metal powders. The processes involved in the handling of Hexafluorosilicic Acid are variable in relation to enclosure. Some processes are fully enclosed while others are open. Some processes are continuous while others are batch processes. Some are indoors while others are outdoors. In all cases specialized dedicated machinery is used. Due to the hazardous and corrosive nature of Hexafluorosilicic acid trioxide the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to use of HFS Acid during the manufacture of metals. Contributing Worker Scenarios: Worker exposure arising due to day to day use in closed processes with no likelihood of exposure, day to day use in closed batch processes and in batch processes where there is some potential for exposure and use in the production of metal powders by wet methods. 2.1


Environmental exposure arising due to metal manufacturing use of HFS acid.


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Section 2.1 describes the environmental releases that may occur during the metal manufacturing use of HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions from industrial sources are monitored and controlled. Liquid wastes from industrial sites would generally be treated prior to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to a maximum of 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. For metal manufacturing use the values in the STP effluent may be below this due to the small on-site tonnages however any emissions should not exceed this value as a general rule. Sludge from the waste metal manufacturing plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Metal manufacturing sites may use up to a largest individual site value of 788 tonnes per annum as a worst case assumption. Regional tonnage is expected to be 1,000 tonnes as a worst case assumption. According to manufacturer information the number of emission days per year is 330. Frequency and duration of use

Frequency of use is estimated to be 220 days per year, with a standard 8 hour working day.




Use of HFS acid during the manufacture of metals takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Technical conditions and measures at process level (source) to prevent release

Metal manufacturing use is carried out indoors or outdoors in dedicated facilities and direct losses to surface water or the municipal STP should be prevented. With regards to environmental emissions the loss of fluoride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture fluoride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Industrial waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from metal manufacturing use or from the onsite WWTP should not exceed 131 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Waste water from wide dispersive uses does not need to be treated. Organizational measures to prevent/limit releases from site





There is no envisaged external recovery of waste. Waste industrial WWTP sludge is reduced and then incinerated or sent to


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landfill and emissions to air are not collected.

2.2


Worker exposure arising due to day to day use in closed processes with no likelihood of exposure during the metal manufacturing use process. Section 2.2 describes the potential exposure to workers during the metal manufacturing use of HFS acid from operation of closed systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. Workers involved in metal manufacture use of HFS Acid, handling, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Metal manufacturing sites may use up to a largest individual site value of 788 tonnes per annum. Use of HFS Acid in the metal manufacture process may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during metal manufacturing use is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, cleaning and maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the metal manufacturing use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the storage vessels and operation of the metal manufacturing equipment takes place under controlled conditions whenever possible. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid.


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Technical conditions to control dispersion from source towards worker


Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of the workers. Conditions and measures related to personal protection, hygiene and health.


Contributing scenario 3 controlling worker exposure due day to day use in closed batch processes and in batch processes where there is some potential for exposure (such as sampling)

Worker exposure arising due to day to day use in closed batch processes and in batch processes where there is some potential for exposure (such as sampling). Section 2.3 describes the potential exposure to workers during the metal manufacturing use of HFS acid from operation of batch metal manufacturing systems. These may be closed or with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. The potential exposure arises from the operation of the metal manufacturing equipment and its associated machinery. Workers involved in metal manufacturing, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Metal manufacturing sites may metal manufacturing use up to a largest individual site value of 788 tonnes per annum.


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for


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exposure during metal manufacturing use is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, maintenance and cleaning are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the metal manufacturing use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the metal manufacturing use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the storage vessels and operation of the metal manufacturing equipment takes place under controlled conditions whenever possible. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker




Contributing scenario 4 controlling worker exposure for manufacture of metal powders in wet processes

Worker exposure arising due to manufacture of metal powders in wet processes.

Section 2.4 describes the potential exposure to workers during day to day use of HFS Acid for metal powder manufacturing in wet processes. Potential exposure may occur during the day to day use of machinery however it is more likely to occur during tasks associated with sampling of solutions, cleaning and routine maintenance. Workers involved in metal powder manufacturing, handing, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation.


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The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Metal manufacturing sites may metal manufacturing use up to a largest individual site value of 788 tonnes per annum.


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during metal manufacturing use is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the metal powder manufacturing use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the metal manufacturing use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the storage vessels and operation of the metal manufacturing equipment takes place under controlled conditions whenever possible. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker



Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the manufacture of metal powders in wet processes. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid.


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Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 6 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 6. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 6 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 6 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 6. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th

(worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 6 are shown in the tables below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP could be considered during derivation of the values below for industrial use scenarios for large tonnage sites however this was not formally required for the relatively small tonnages associated with metal manufacturing use. In all cases removal in the WWTP should be 90% or greater. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


6b Effluent (in mg/L) 2

ERC Compartments Concentration aquatic (mg/L)

Freshwater (in mg/L) 0.241 8a Marine water (in mg/L) 0.024



ERC Compartments Concentration 8a


0.194


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0.016


0.003 8b


0.0003


0.177 6b


0.017



1.64 6b





0.0788 0.0788



PNEC mg/L

PEC/PNEC Comments





PNEC mg/kg

PEC/PNEC Comments



PNEC mg/kg

PEC/PNEC Comments


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Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with metal manufacturing and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety shower should also be located in the area of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial metal manufacturing and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration All 480 min


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Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction 1, 3 Substantial (10-50%) 27b 0.1% Primary emission source proximity 1, 3, 27b Primary emission source is not located in the breathing zone


Activity class 1, 3 Transfer of liquid products 27b Activities with open liquid surfaces -activities with agitated

surfaces Containment 1, 3 Handling reduces contact between product and adjacent air,

controlled loading 3 Submerged loading Localised controls 3, 27b Vapour recovery systems; LEV 1 LEV Segregation 1, 27b Complete segregation of workers in separate control room 3, Partial segregation of workers Fugative emission source 1, 27b Process fully enclosed – not openly breached for sampling 3 Not fully enclosed – effective housekeeping practices in place. Dispersion 1, 27b Outdoors not close to buildings 3 Outdoors close to buildings 1, 3, 27b Indoors, any sized room, only good natural ventilation










Indoor CES 2 1 Liquid 3.7 x10-01 1.2 4.5 x10-01 1 CES 3 3 Liquid 2.2 x10-01 4.0 x10-01 2.7 x10-01 6.2 x10-01 CES 4 27b Liquid 2.7 x10-01 8.6 x10-01 3.3 x10-01 7.6 x10-01 Outdoor CES2 1 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02 CES 3 3 Liquid 7.2 x10-02 4.8 x10-01 1.7 x10-01 4 x10-01 CES 4 27b Liquid 8.9 x10-03 5.9 x10-02 2.2 x10-02 5.0 x10-02





DNEL (mg/m3)


PROC 1 indoor

1.2 3.8 x10-01 CES 2

PROC 1 outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 3 indoor

4.0 x10-01 2.2 x10-01

Acute effects

CES 3

PROC 3 outdoor

4.8 x10-01


3.125

1.5 x10-01


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PROC 27b indoor

8.6 x10-01 CES 4

PROC 27b outdoor

5.9 x10-02


3.125

1.9 x10-02

PROC 1 indoor

1 5.3 x10-01 CES 2

PROC 1 outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 3 indoor

6.2 x10-01 3.3 x10-01 CES 3

PROC 3 outdoor

4 x10-01


1.88

2.1 x10-01

PROC 27b indoor

7.6 x10-01 4.0 x10-01

Long term effects

CES 4

PROC 27b outdoor

5.0 x10-02


1.88

2.4 x10-02

4



• Local emission to air less than 131 kg per day for an industrial site. Regional emissions should not exceed 13,700 kg per day in total.

• When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the industrial waste-water stream should be reduced to 7.3 mg/L maximum using fluoride







above.


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Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 7: Use of HFS Acid in washing and cleaning products.

1

Exposure Scenario 7

Use of HFS Acid in washing and cleaning products. Processes Covered: Environmental Releases ERC8b: Wide dispersive indoor use of reactive substances in open systems Worker Processes PROC07: Industrial spraying PROC09: Transfer of formulations to small containers. PROC10: Roller application or brushing of coatings PROC11: Non-industrial spraying PROC19: Low energy hand mixing with intimate contact and only PPE available. Hexafluorosilicic Acid is used as a component in washing and cleaning solutions. The processes involved in the handling of Hexafluorosilicic Acid during industrial use of these products are variable in relation to enclosure. Some processes are fully enclosed while others are open. Some processes are continuous while others are batch processes. Some are indoors while others are outdoors. In all cases specialized dedicated machinery is used. Due to the hazardous and corrosive nature of Hexafluorosilicic acid trioxide the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to use of HFS Acid in washing and cleaning products. Contributing Worker Scenarios: Worker exposure arising due to industrial spraying, transfer to small containers, roller and brushing application of coatings and hand mixing and non-industrial spraying. 2.1


Environmental exposure arising due to use of HFS acid in washing and cleaning products.

Section 2.1 describes the environmental releases that may occur during the use of HFS acid in washing and cleaning products. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions from industrial sources are generally monitored and controlled. Liquid wastes from industrial sites would generally be treated prior to emission to remove any Hexafluorosilicic Acid in the waste water. However as this use is a wide dispersive use and on-site tonnages are very small these risk management measures are no required in order to demonstrate safe use for the environment. Sludge from the waste washing and cleaning plant is sent for recovery, incineration or landfill and is not used for agricultural


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spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Sites that use HFS Acid in washing and cleaning products may use up to a largest individual site value of 2 tonnes per annum as a worst case assumption though actual on-site tonnages are expected to be much less in reality. The regional tonnage is considered to be around 1,000 tonnes per year. As a wide dispersive use 365 emission days per year are expected. Frequency and duration of use

Frequency of use is estimated to 365 days per year for a wide dispersive use. .


Flow rate of receiving water at least 18,000 m3 per day. Dilution of STP emissions at least 10 fold. Wide dispersive release.


Use of HFS acid during industrial washing and cleaning takes place in indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions; with transfer pipelines either fully or partially closed systems. Emission via wastewater is generally limited by on-site WWTP processes though this is not formally required for small on-site tonnages. Technical conditions and measures at process level (source) to prevent release

Washing and cleaning use of HFS Acid is carried out indoors or outdoors in industrial facilities and direct losses to surface water or the municipal STP should be prevented. With regards to environmental emissions the loss of fluoride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture fluoride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Industrial waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from washing and cleaning use or from the onsite WWTP should not exceed 3 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Waste water from wide dispersive uses does not need to be treated. Organizational measures to prevent/limit releases from site

Workers are fully trained in order to prevent accidental release and emissions may be monitored to ensure airborne concentrations are within acceptable levels. Conditions and measures related to municipal STP





Contributing scenario 2 controlling worker exposure for industrial spraying.

Worker exposure arising due to day to day use in industrial spraying processes.

Section 2.2 describes the potential exposure to workers during the use of HFS Acid in industrial spraying of cleaning and washing products. Appropriate PPE and onsite control parameters are in place to limit the risk of exposure to workers


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involved in this task.



Sites that use HFS Acid in washing and cleaning products may use up to a largest individual site value of 2 tonnes per annum as a worst case assumption though actual on-site tonnages are expected to be much less in reality. The regional tonnage is considered to be around 1,000 tonnes per year. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during washing and cleaning use is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the use of HFS acid indoors in the spraying of cleaning and washing products, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the washing and cleaning use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the operation of the washing and cleaning equipment takes place under controlled conditions whenever possible. The use of Hexafluorosilicic is performed only horizontally or downward with no or low compressed air during industrial spraying. The use of Hexafluorosilic Acid is carried out only downward with no or low compressed air during non industrial spraying. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker



Workers may potentially be exposed to HFS acid when operating cleaning equipment (e.g. sprayer, brushes). All operations are performed in a controlled manner where possible. The use of Hexafluorosilicic is performed only horizontally or downward with no or low compressed air during industrial spraying. The use of Hexafluorosilic Acid is carried out only downward with no or low compressed air during non industrial spraying. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid products are stored in closed containers and tanks and transferred under contained conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid.


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Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.3



Section 2.3 describes the potential exposure to workers during the filling of small containers in dedicated filling lines. Potential exposure is most likely to occur during tasks associated with the actual filling of the containers themselves. Appropriate PPE and onsite control parameters are in place to limit the risk of exposure to workers involved in this task. Product characteristics



Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during washing and cleaning use is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the washing and cleaning use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release


Full system control should be in place during indoor operations when natural ventilation is not sufficient. Reactors and


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pipelines should be closed and sealed systems where possible.

Organizational measures to prevent/limit release


Workers may potentially be exposed to HFS acid when operating transfer equipment (e.g. valves, pumps). All operations are performed in a controlled manner where possible. The use of Hexafluorosilicic is performed only horizontally or downward with no or low compressed air during industrial spraying. The use of Hexafluorosilic Acid is carried out only downward with no or low compressed air during non industrial spraying. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid products are stored in closed containers and tanks and transferred under contained conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. Good occupational hygiene and exposure control measures are implemented to minimise the potential for professional worker exposure. Workers involved in the wide dispersive industrial uses of HFS acid are well-trained in the required procedures and use of appropriate protective equipment. 2.4

Contributing scenario 4 controlling worker exposure for roller and brushing applications of coatings

Worker exposure arising due to roller and brushing applications of coatings

Section 2.4 describes the potential exposure to workers during the industrial uses of HFS Acid during roller and brushing applications to surfaces. Appropriate PPE and onsite control parameters are in place to limit the risk of exposure to workers involved in this task. Product characteristics


Sites that use HFS Acid in washing and cleaning products may use up to a largest individual site value of 2 tonnes per annum as a worst case assumption though actual on-site tonnages are expected to be much less in reality. The regional tonnage is considered to be around 1,000 tonnes per year. As a wide dispersive use 365 emission days per year are expected. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during roller and brush application to surfaces is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


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Workers are fully trained in safe use and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of workers. During the use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the use of HFS acid in roller or bush application to surfaces. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release




Workers may potentially be exposed to HFS acid when operating cleaning equipment (e.g.rollers, brushes). All operations are performed in a controlled manner where possible. The use of Hexafluorosilicic is performed only horizontally or downward with no or low compressed air during industrial spraying. The use of Hexafluorosilic Acid is carried out only downward with no or low compressed air during non industrial spraying. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid products are stored in closed containers and tanks and transferred under contained conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. Good occupational hygiene and exposure control measures are implemented to minimise the potential for professional worker exposure. Workers involved in the wide dispersive industrial uses of HFS acid are well-trained in the required procedures and use of appropriate protective equipment. 2.5

Contributing scenario 5 controlling worker exposure for hand mixing with intimate contact and PPE only

Worker exposure arising due to hand mixing with intimate contact and PPE only.

Section 2.5 describes the potential exposure to workers during the use of HFS acid in the hand mixing of formulations (with intimate contact and PPE only). Appropriate PPE and onsite control parameters are in place to limit the risk of exposure to workers involved in this task. Product characteristics

HFS acid is a liquid at room temperature and pressure with a typical purity of around 95% (range 80 – 100%). It is a fuming liquid with a strong pungent odour. The vapour pressure of a 10 % aqueous solution of hexafluorosilicic acid is reported to be 2.30 kPa at 20 degrees Celsius. (REACH Centre, 2010). The vapour pressure of a 35% aqueous solution of hexafluorosilicic acid is reported to be 30 hPa at 20 degrees Celsius.


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However the reported vapour pressure is considered likely to be attributable to the release of hydrogen fluoride vapour (IPCS, 2004). HFS acid is miscible in water and decomposes upon heating. Amounts used


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during hand mixing of formulations is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management

Respiration volume under conditions of use: 10 m3/d Area of skin contact with the substance under conditions of use: 480cm2 (ECETOC default). Other operational conditions affecting environmental exposure

Use of HFS acid during hand mixing of formulations takes place in indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is generally limited by on-site WWTP processes though this is not formally required for small on-site tonnages. Technical conditions and measures at process level (source) to prevent release




Workers may potentially be exposed to HFS acid when operating cleaning and mixing equipment (e.g. mixing equipment, brushes). All operations are performed in a controlled manner where possible. The use of Hexafluorosilicic is performed only horizontally or downward with no or low compressed air during industrial spraying. The use of Hexafluorosilic Acid is carried out only downward with no or low compressed air during non industrial spraying. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid products are stored in closed containers and tanks and transferred under contained conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.


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Good occupational hygiene and exposure control measures are implemented to minimise the potential for professional worker exposure. Workers involved in the wide dispersive industrial uses of HFS acid are well-trained in the required procedures and use of appropriate protective equipment. 2.6

Contributing scenario 6 controlling worker exposure for (non-industrial) professional spraying

Worker exposure arising due to professional spraying and air dispersive techniques

Section 2.6 describes the potential exposure to workers during the professional end use of HFS Acid in cleaning and washing products for spray applications. Appropriate PPE and onsite control parameters are in place to limit the risk of exposure to workers involved in this task. Product characteristics



Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during non-industrial spraying of washing and cleaning use is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the washing and cleaning use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release




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Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zones of workers. Conditions and measures related to personal protection, hygiene and health.

Professional use of sprayed HFS Acid cleaning solutions during air dispersive applications involves special equipment and high integrity specialized systems. Workers may potentially be exposed to HFS acid when operating cleaning equipment (e.g. sprayers, brushes). All operations are performed in a controlled manner where possible. The use of Hexafluorosilicic is performed only horizontally or downward with no or low compressed air during industrial spraying. The use of Hexafluorosilic Acid is carried out only downward with no or low compressed air during non industrial spraying. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid products are stored in closed containers and tanks and transferred under contained conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. Good occupational hygiene and exposure control measures are implemented to minimise the potential for professional worker exposure. Workers involved in the wide dispersive industrial uses of HFS acid are well-trained in the required procedures and use of appropriate protective equipment. 3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 7 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 7. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 7 for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 7 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 7. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 7 are shown in the tables below. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


8b Effluent (in mg/L) 0.052

ERC Compartments Concentration aquatic (mg/L)



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ERC Compartments Concentration Freshwater sediment (in mg/kg)

0.0043 8b


0.0004



2.2 x 10-5 8b

Groundwater (in mg/L) 5.4 x 10-5




3.98 x 10-6 2.45 x 10-6


Compartment

PEC mg/L

PNEC mg/L

PEC/PNEC Comments

Tier 1 Freshwater 0.0052 0.9 0.0058 Safe use demonstrated in tier 1

Compartment PEC mg/kg

PNEC mg/kg

PEC/PNEC Comments

Tier 1 Soil 2.2 x 10-5 11 1.8 x 10-6 Safe use demonstrated in tier 2

Compartments PEC (mg/L) PNEC (mg/L)

PEC/PNEC Comments

Tier 1 STP 0.052 51 0.001 Safe use in tier 1

Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenarios associated with washing/cleaning and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are


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equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should also be located in the areas of use in case of accidental spillage.The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial metal manufacturing and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration 9 480 min 7 and 10 240 min 11 and 19 120 minutes Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction 7, 9, 10, 19 Substantial (10-50%) 11 Small (1-5%) Very small (0.5-1%) Primary emission source proximity 7, 9, 10, 11,

19 Primary emission source is located in the breathing zone of the worker

Activity class 9 Transfer of liquid products 7 Industrial spraying (air dispersive techniques) –horizontal and

downward spraying (low application rate 0.03-0.3L/min and very low application rate <0.03L/min)

11 Non industrial spraying horizontal and downward (low application rate 0.03-0.3L/min)


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10 Roller application or brushing – spreasing of surfaces 0.3-1 m2/hr

19 Hand-mixing with intimate contact and only PPE available – activities with open liquid – undisturbed surfaces (no aerosol formation) – open surface 0.1 -0.3 m2 and open surface 0.3-1 m2

Containment 9 Handling reduces contact between product and adjacent air, controlled loading, submerged loading

7, 10, 11, 19 Not applicable Localised controls 9 LEV – enclosing hoods 7, 10 LEV – capturing hoods 11, 19 Not applicable Fugative emission source 9 Process fully enclosed – not openly breached for sampling 7, 10, 11, 19 Process not fully enclosed but effective housekeeping

practises are in place Dispersion 9 Outdoors not close to buildings 7 Outdoor not close to buildings and indoors, down-flow spray

room 10, 11, 19 Outdoor not close to buildings and indoors, any sized room 9 Indoors, any sized room, only good natural ventilation










Indoor CES 2 9 Liquid 4.4 x10-01 1.4 5.4 x10-01 1.2 CES 3 7 Liquid 13 41 16 37 CES 4 10 Liquid 7.5 23 8.9 21 CES 5 19 Liquid 12 39 15 34 CES 6 11 Liquid 9.2 29 11 26 Outdoor Loading/transfer (Small containers)

9 Liquid 7.2 x10-02 4.7 x10-01 1.7 x10-01 4 x10-01

Industrial spraying 7 Liquid 4 27 9.5 22 Roller application or brushing

10 Liquid 4 26 9.6 23

Non industrial spraying 19 Liquid 6.7 44 16 37 Hand-mixing with intimate contact

11 Liquid 2 13 4.8 11


Exposure details



DNEL (mg/m3)


PROC 7 indoor

41 0.66* CES 2

PROC 7 outdoor

27


3.125

0.43*

Acute effects

CES 3 PROC 9 indoor

1.4 Respiratory irritation and

3.125 4.5 x10-01


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PROC 9 outdoor

4.7 x10-01 corrositivity 1.5 x10-01

PROC 10 indoor

23 0.37* CES 4

PROC 10 outdoor

26


3.125

0.42*

PROC 19 indoor

39 0.70* CES 5

PROC 19 outdoor

44


3.125

0.62*

PROC 11 indoor

29 0.46* CES 6

PROC 11 outdoor

13


3.125

0.21*

PROC 7 indoor

37 0.98* CES 2

PROC 7 outdoor

22


1.88

0.59*

PROC 9 indoor

1.2 6.4 x10-01 CES 3

PROC 9 outdoor

4 x10-01


1.88

2.2 x10-01

PROC 10 indoor

21 0.56* CES 4

PROC 10 outdoor

23


1.88

0.61*

PROC 19 indoor

34 0.90* CES 5

PROC 19 outdoor

37


1.88

0.98*

PROC 11 indoor

26 0.69*

Long term effects

CES 6

PROC 11 outdoor

11


1.88

0.29*

4



• Local emission to air less than 3 kg per day for an industrial site. Regional emissions should not exceed 13,700 kg per day in total.


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• When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the industrial waste-water stream should be reduced to 7.3 mg/L maximum using fluoride







above.


Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 8: use of HFS Acid in the manufacture of chemicals. 1

Exposure Scenario 8

Use of HFS Acid in the manufacture of chemicals. Processes Covered: Environmental Releases ERC02: Formulation of preparations ERC04: Industrial use of processing aids ERC:6a: Industrial use of intermediates Worker Processes PROC01: Use in closed process, no likelihood of exposure. PROC02: Use in closed, continuous process with occasional controlled exposure. PROC03: Use in closed batch processes. PROC08b: Transfer of substance or preparation (charging/discharging) from/to vessels/large containers at dedicated facilities. PROC09: Transfer of formulations to small containers. PROC27b: Manufacture of metal powders by wet processes. The processes involved in the manufacture of chemicals using Hexafluorosilicic Acid are variable in relation to enclosure. Some processes are fully enclosed while others are open. Some processes are continuous while others are batch processes. Some are indoors while others are outdoors.


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During the process of chemical manufacture Hexafluorosilicic Acid is used at dedicated industrial facilities and the associated environmental emissions are extremely limited (almost no emissions) and are generally treated on-site before release to the waste system. Waste acid would primarily be directed to the waste stream and facilities would generally be expected to have dedicated off-gas and effluent treatment facilities. Given that upon contact with water Hexafluorosilicic Acid converts to ions and is fully miscible in water its actual conversion, neutralisation and removal from the waste stream is expected to be extremely rapid and as such removal estimates presented in EUSES below are to be considered conservative. Due to the hazardous and corrosive nature of Hexafluorosilicic Acid the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to manufacture of chemicals using of HFS acid. Contributing Worker Scenarios: Worker exposure arising due to day to day use in closed processes with no likelihood of exposure, day to day use in closed continuous and batch processes with occasional exposure (such as sampling), transfer of substance to and from vessels and containers, transfer of formulations to small containers and production of metal powders by wet processes. 2.1


Environmental exposure arising due to manufacture of chemicals using of HFS acid.

Section 2.1 describes the environmental releases that may occur during the manufacture of chemicals using HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions are monitored and controlled. Liquid wastes would generally be treated (neutralisation to neutral pH and/or precipitation) prior to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. Sludge from the waste water treatment plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Chemical production sites may manufacture up to a largest individual site value of 23,000 tonnes per annum, with approximately 46,000 tonnes produced per year in the EU. According to the guidance for this tonnage band, the default REACH number of emission days per year is 330. Frequency and duration of use





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Production takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Manufacturing processes may be indoor or outdoor. Technical conditions and measures at process level (source) to prevent release

Manufacture of chemicals using HFS Acid is carried out indoors or outdoors in dedicated facilities and losses to surface water or the municipal STP should be prevented by on site WWTP removal. With regards to environmental emissions the loss of fluoride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture fluoride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from manufacturing or from the onsite WWTP should not exceed 1,740 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Organizational measures to prevent/limit releases from site







Worker exposure arising due to day to day use in closed processes with no likelihood of exposure during the manufacturing process. Section 2.2 describes the potential exposure to workers during the manufacture of chemicals using of HFS acid from operation of closed systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. The potential exposure arises from the operation of the reactor and its associated machinery. Workers involved in production, handling, sampling and transfer of materials are trained in the procedures and the use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics

HFS acid is a liquid at room temperature and pressure with a typical purity of around 95% (range 80 – 100%). It is a fuming liquid with a strong pungent odour. The vapour pressure of a 10 % aqueous solution of hexafluorosilicic acid is reported to be 2.30 kPa at 20 degrees Celsius. (REACH Centre, 2010). The vapour pressure of a 35% aqueous solution of hexafluorosilicic acid is reported to be 30 hPa at 20 degrees Celsius.


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However the reported vapour pressure is considered likely to be attributable to the release of hydrogen fluoride vapour (IPCS, 2004). HFS acid is miscible in water and decomposes upon heating. Amounts used

Chemical production sites may manufacture up to a largest individual site value of 23,000 tonnes per annum, with approximately 46,000 tonnes produced per year in the EU. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during manufacture is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, maintenance and cleaning are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the manufacture of chemicals using of HFS acid indoors, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the manufacture or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release





Contributing scenario 3 controlling worker exposure due to day to day use in closed continuous and batch processes with occasional exposure (such as sampling)

Worker exposure arising due to day to day use in closed continuous and batch processes with occasional exposure (such as sampling).


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Section 2.3 describes the potential exposure to workers during the manufacture of chemicals using of HFS acid from operation of closed batch and continuous systems with occasional potential for exposure during tasks such as sampling, maintenance and cleaning. The potential exposure arises from the operation of the reactor and its associated machinery. Workers involved in production, handling, sampling and transfer of materials are trained in the procedures and the use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Chemical production sites may manufacture up to a largest individual site value of 23,000 tonnes per annum, with approximately 46,000 tonnes produced per year in the EU. Production may be continuous or batch process based. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during manufacture is generally considered to be of short duration, with limited potential for exposure. Tasks such as sampling, maintenance and cleaning are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the manufacture of chemicals using of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the manufacture or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the reactor or production vessels and the operation of the reactor vessel itself takes place under controlled conditions. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid.


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Technical conditions to control dispersion from source towards worker






Section 2.4 describes the potential exposure to workers during the transfer of manufactured of HFS acid to and from large sized vessels and containers. The potential exposure arises from the transfer of the substance from the reactor to storage areas or vessels. Workers involved in this transfer of the substance will be exposed in the manual handling of the substance to storage vessels and potentially during the loading of road and rail tankers. Large tanks are generally bottom filled. Workers involved in transfer of materials to and from these large sized containers and vessels are trained in the procedures and the use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics



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During the transfer and loading of HFS acid indoors, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the manufacture or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release




Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of produced HFS acid to and from vessels and containers at dedicated facilities. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.5



Section 2.5 describes the potential exposure to workers during the filling of small containers in dedicated filling lines. Potential exposure is most likely to occur during tasks associated with the actual filling of the containers themselves. Workers involved in transfer of materials to small containers in dedicated filling lines trained are in the procedures and the use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the


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breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. Submerged loading may be used when needed. Vapour recovery systems and local exhaust ventilation such as enclosing hoods are used where required. Emission sources can be completely or partially segregated from the work environment by isolating the source in a fully enclosed and separate room and using complete personal enclosure with ventilation where necessary. The processes are generally fully enclosed (air tight) and the integrity of the enclosure is monitored. However there may be some processes that are not-fully enclosed which require good housekeeping practices only. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics





During the transfer of HFS acid indoors, local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the manufacture or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release





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Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the transfer of HFS acid to small containers in a dedicated filling line. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 2.6

Contributing scenario 6 controlling worker exposure for production of metal powders by wet processes

Worker exposure arising due to manufacture of metal powders in wet processes.

Section 2.6 describes the potential exposure to workers during day to day use of HFS Acid for metal powder manufacturing in wet processes. Potential exposure may occur during the day to day use of machinery however it is more likely to occur during tasks associated with sampling of solutions, cleaning and routine maintenance. Workers involved in metal powder manufacturing, handling, sampling and transfer of materials are trained in the procedures and the use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Chemical production sites may manufacture up to a largest individual site value of 23,000 tonnes per annum, with approximately 46,000 tonnes produced per year in the EU. Production may be continuous or batch process based.


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during production of metal powder in wet processes is generally considered to be of short duration, with limited potential for exposure. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


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During the metal powder manufacturing use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the metal manufacturing use or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release

If being carried out indoors the transfer of the substance from the storage vessels and operation of the metal powder manufacturing equipment takes place under controlled conditions whenever possible. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Technical conditions to control dispersion from source towards worker


Workers are fully trained in safe use of equipment and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of the workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the manufacture of metal powder in wet processes. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.

3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 8 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 8. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 8 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 8 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 8. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 8 are shown in the tables below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP was considered during derivation of the values below. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


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Estimated exposure concentrations

ERC Compartment:

value unit Freshwater (in mg/L) 0.738 mg/L

2

Marine water (in mg/L) 0.066 mg/L

Freshwater (in mg/L) 0.755 mg/L 4


Freshwater (in mg/L) 0.738 mg/L 6a



ERC Compartment:

value unit Freshwater sediment (in mg/kg) 0.593 mg/L

2

Marine sediment (in mg/kg) 0.059 mg/L

Freshwater sediment (in mg/kg) 0.607 mg/L 4


Freshwater sediment (in mg/kg) 0.593 mg/L 6a



ERC ERC for Compartment:

value unit Agricultural soil (averaged over 30 days (in mg/kg)

0.376 mg/L 2

Groundwater (in mg/L) 1.34 mg/L


3.85 mg/L 4



0.206 mg/L 6a


ERC Local concentration PEC air

(local+regional) 2 Annual average PEC in air, total (mg/m3) 0.438 0.438 4 Annual average PEC in air, total (mg/m3) 16.6 16.6


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6a Annual average PEC in air, total (mg/m3) 0.976 0.976



PNEC mg/L

PEC/PNEC Comments

2 Tier 2 Freshwater 0.738 0.9 0.82 Safe use demonstrated in tier 2

4 Tier 2 Freshwater 0.755 0.9 0.84 Safe use demonstrated in tier 2


ERC Compartment PEC mg/kg

PNEC mg/kg

PEC/PNEC Comments

2 Tier 2 Soil 0.376 11 0.034 Safe use demonstrated in tier 2

4 Tier 2 Soil 3.85 11 0.35 Safe use demonstrated in tier 2

6a Tier 2 Soil 0.206 11 0.018 Safe use demonstrated in tier 2

ERC Compartments PEC (mg/L) PNEC (mg/L) PEC/PNEC Comments

2 Tier 2 STP 7.3 51 0.143 In the second tier assessment all waste acid is treated before any possible release to a municipal STP or any biological phase of an STP. As such there is no indicated risk.

4 Tier 2 STP 7.3 51 0.143

6a Tier 2 STP 7.3 51 0.143

Worker exposure

Assessment of dermal risk


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During the processes that will be carried out for all the exposure scenarios associated with production and use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should be in place in areas of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial production and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration All 480 min Product type All Liquid Process temperature All Room temperature (15-25oC) Vapour pressure All 2300 pa Liquid weight fraction 1, 2, 3, 8b, 9 Substantial (10-50%) 27b 0.1% Primary emission source proximity 1, 2, 3, 8b,

27b Primary emission source is not located in the breathing zone of the worker - the assessment for this activity involves a primary far-field emission source only (workers are in a


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control room) 9 Primary emission source is located in the breathing zone of

the worker Activity class 1, 2, 3, 8b, 9 Transfer of liquid products 27b Activities with open liquid surfaces -activities with agitated

surfaces Containment 1, 2, 3, 9 Handling reduces contact between product and adjacent air,

controlled loading 3, 9 Submerged loading 8b n/a due to bottom loading or tankers Localised controls 3, 27b Vapour recovery systems; LEV 1, 2, 8b, 9 LEV Segregation 1, 2, 27b Complete segregation of workers in separate control room 3, 8b Partial segregation of workers Fugative emission source 1, 8b, 9, 27b Process fully enclosed – not openly breached for sampling 3, 2 Not fully enclosed – effective housekeeping practices in place. Dispersion 1, 2, 8b, 9,

27b Outdoors not close to buildings

3 Outdoors close to buildings 1, 2, 3, 8b, 9,

27b Indoors, any sized room, only good natural ventilation










Indoor CES 2 1 Liquid 3.7 x10-01 1.2 4.5 x10-01 1

2 Liquid 3.7 x10-01 1.2 4.5 x10-01 1 CES 3 3 Liquid 2.2 x10-01 4.0 x10-01 2.7 x10-01 6.2 x10-01

CES 4 8b Liquid 3.7 x10-01 1.2 4.5 x10-01 1 CES 5 9 Liquid 4.4 x10-01 1.4 5.4 x10-01 1.2 CES 6 27b Liquid 2.7 x10-01 8.6 x10-01 3.3 x10-01 7.6 x10-01 Outdoor

1 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02 CES 2 CES 3 2 Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02 3 Liquid 7.2 x10-02 4.8 x10-01 1.7 x10-01 4 x10-01 CES 4 8b Liquid 2.4 x10-03 1.6 x10-02 5.8 x10-03 1.4 x10-02 CES 5 9 Liquid 7.2 x10-02 4.7 x10-01 1.7 x10-01 4 x10-01 CES 6 27b Liquid 8.9 x10-03 5.9 x10-02 2.2 x10-02 5.0 x10-02





DNEL (mg/m3)


PROC 1 indoor

1.2 3.8 x10-01 Acute effects CES 2

PROC 1 outdoor

1.6 x10-02


3.125

5.1 x10-03


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PROC 2 indoor

1.2 3.125 3.8 x 10-01 CES 3

PROC 2 outdoor

1.6 x 10-02


PROC 3 indoor

4.0 x10-01 2.2 x10-01 CES 4

PROC 3 outdoor

4.8 x10-01


3.125

1.5 x10-01

PROC 8a indoor

1.2 3.8 x10-01

PROC 8a outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 8b indoor

1.2 3.8 x10-01

CES 5

PROC 8b outdoor

1.6 x10-02


3.125

5.1 x10-03

PROC 9 indoor

1.4 4.5 x10-01 CES 6

PROC 9 outdoor

4.7 x10-01


3.125

1.5 x10-01

PROC 15 indoor

4.6 x10-01 1.5 x10-01 CES 7

PROC 15 outdoor

-


3.125

-

PROC 1 indoor

1 5.3 x10-01 CES 2

PROC 1 outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 2 indoor

1 5.3 x 10-03 CES 3

PROC 2 outdoor

1.4 x 10-02


1.88

7.4 x 10-03

PROC 3 indoor

6.2 x10-01 3.3 x10-01 CES 4

PROC 3 outdoor

4 x10-01


1.88

2.1 x10-01

PROC 8a indoor

1 5.3 x10-01

PROC 8a outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 8b indoor

1 5.3 x10-01

CES 5

PROC 8b outdoor

1.4 x10-02


1.88

7.4 x10-03

PROC 9 indoor

1.2 6.4 x10-01 CES 6

PROC 9 outdoor

4 x10-01


1.88

2.2 x10-01

PROC 15 indoor

4.1 x10-01 Respiratory irritation and corrositivity

1.88 2.2 x10-01

Long term effects

CES 7

PROC 15 outdoor

- -

4



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above.


Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 9: laboratory use of HFS acid. 1

Exposure Scenario 9

Laboratory use of HFS acid Processes Covered: Environmental Releases ERC8a: Wide dispersive indoor uses of processing aids in open systems ERC8b: Wide dispersive indoor uses of reactive substances in open systems Worker Processes PROC15: Laboratory use. This is a wide dispersive use and environmental emissions of Hexafluorosilicic Acid in waste water generated from laboratory use are extremely limited (almost no emissions). Given that upon contact with water Hexafluorosilicic Acid


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converts to ions and is fully miscible in and the fact that it is added in very small amounts the estimated concentrations in the environment as calculated in EUSES below are to be considered conservative. The processes involved in the handling of HFS acid as a laboratory chemical are open batch processes that are conducted indoors. Due to the hazardous and corrosive nature of Hexafluorosilicic Acid the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to laboratory use of HFS acid. Contributing Worker Scenarios: Worker exposure arising due to laboratory use of HFS acid. 2.1


Environmental exposure arising due to laboratory use of HFS acid.

Section 2.1 describes the environmental releases that may occur during the laboratory use of HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. As a wide dispersive use specific risk management measures are not required for this exposure scenario however good practice in the handling and emission of chemicals should be employed to reduce losses of HFS Acid. Product characteristics


Actual amounts onsite are expected to be very small with amounts of 1kg or 1 litre specified by the PROC. However as a worst case assumption the on-site tonnage for this CES is considered to be 0.2 tonnes per annum. Regional tonnage is assumed to be a worst case of 100 tonnes per annum. As a wide dispersive use the default REACH number of emission days of 365 is considered. Frequency and duration of use

Frequency of use for workers is estimated to be 220 days per year, with a standard 8 hour working day. Actual use of HFS Acid may be in continuous processes or batch processes and for the environment the default REACH number of emission days of 365 is considered for this wide dispersive use. Environmental factors influenced by risk management



Production takes place in an indoor laboratory with emissions to air and wastewater being controlled. Standard good laboratory practice should be employed to reduce emissions. Technical conditions and measures at process level (source) to prevent release

Laboratory use is carried out indoors in open batch processes at dedicated facilities and losses to surface water or the municipal STP should be prevented where possible. With regards to environmental emissions the loss of fluoride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture fluoride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Waste water should be emitted to the on-site WWTP if possible for specialized removal. Sludge from the on-site WWTP should not be spread to soil. Releases to air should be less than 3 kg per day.


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Organizational measures to prevent/limit releases from site

Laboratory workers are fully trained in order to prevent accidental release and exposures may be monitored to ensure airborne concentrations are within acceptable levels. Conditions and measures related to municipal STP

Direct emissions to the municipal STP should not be made if possible.


Residues may be sent to external waste treatment or should be stored and removed as hazardous waste according to normal laboratory practice Conditions and measures related to external recovery of waste

There is no envisaged external recovery of waste.

2.2


Worker exposure arising due to laboratory use of HFS Acid (small scale non-industrial laboratories).

Section 2.2 describes the potential exposure to workers during laboratory use of HFS acid especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. Potential exposure is most likely to occur during tasks associated with the actual transfer or mixing of the HFS Acid solutions. Workers involved in laboratory based uses of HFS Acid are trained in the procedures of general safe use of chemicals and acids and the use of protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Amounts use in a non-industrial lab setting are likely to be small with less than 1 litre or 1 kilogram present on site..


Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Use of HFS acid is not likely to be this frequent in practice. Human factors not influence by risk management


During the laboratory use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the manufacture or transfer process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release



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Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of the workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when using HFS acid in a laboratory, especially during the filling and loading of small flasks and vessels using non-dedicated filling lines or small scale transfer methods. All operations are performed in a controlled system in open processes. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage.

3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 9 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 9. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 9 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 9 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid in ES 9. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th (worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 9 are shown in the tables below. Environmental exposures were generated using the REACH defaults and the EUSES 2.1 model. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


Waste water before treatment (in mg/L) 0.0027 8a Effluent (in mg/L) 0.0026 Sewage sludge (in mg/kg) 0.0026

Waste water before treatment (in mg/L) 0.00005 Effluent (in mg/L) 0.00005

8b

Sewage sludge (in mg/kg) 0.0005

ERC Compartments PEC (local mg/L)

Freshwater (in mg/L) 2.71 x 10-4


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8a Marine water (in mg/L) 2.17 x 10-5

Intermittent releases to water (in mg/L) NA

Freshwater (in mg/L) 5.42 x 10-5

Marine water (in mg/L) 5.4 x 10-6

8b

Intermittent releases to water (in mg/L) NA

ERC Compartments Concentration 8a


2.18 x 10-4

Marine sediment (in mg/kg) 2.17 x 10-5


4.36 x 10-5 8b Marine sediment (in mg/kg) 4.35 x 10-6



1.46 x 10-6 8a

Groundwater (in mg/L) 5 x 10-6 Agricultural soil (averaged over 30 days (in mg/kg)

2.19 x 10-7 8b

Groundwater (in mg/L) 5.25 x 10-7

ERC Local concentration PEC air (local+regional)

8a Annual average PEC in air, total (mg/m3) 1.52 x 10-6 1.52 x 10-6 8b Annual average PEC in air, total (mg/m3) 1.25 x 10-8 1.25 x 10-8


ERC

Compartment

PEC mg/L

PNEC mg/L

PEC/PNEC Comments

8a Tier 1 Freshwater

2.18 x 10-4 0.9 2.4 x 10-4 Safe use demonstrated in tier 1

8b Tier 1 Freshwater

5.2 x 10-5 0.9 5.7 x 10-5 Safe use demonstrated in tier 1

ERC Compartment PEC mg/kg

PNEC mg/kg

PEC/PNEC Comments

8a Tier 1 Soil 1.46 x 10-6

11 1.3 x 10-7 Safe use demonstrated in tier 1

8b Tier 1 Soil 2.19 x 10-7

11 2 x 10-8 Safe use demonstrated in tier 1

ERC Compartments PEC (mg/L) PNEC (mg/L) PEC/PNEC Comments

8a Tier 1 STP 0.0026 51 5 x 10-5 Safe use in tier 1


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8b Tier 1 STP 0.00005 51 1 x 10-6 Safe use in tier 1

Worker exposure

Assessment of dermal risk During the processes that will be carried out during tasks associated with laboratory use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should be available in areas of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial production and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration 15 480 min Product type 15 Liquid


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Process temperature 15 Room temperature (15-25oC) Vapour pressure 15 2300 pa Liquid weight fraction 15 Substantial (10-50%) Primary emission source proximity 15 Primary emission source is located in the breathing zone of

the worker Activity class 15 Transfer of liquid products Containment 15 Open process Localised controls 15 LEV Fugative emission source 15 Not fully enclosed – effective housekeeping practices in place. Dispersion 15 Indoors, any sized room, only good natural ventilation










Indoor CES 2 15 Liquid 1.5 x10-01 4.6 x10-01 1.8 x10-01 4.1 x10-01





DNEL (mg/m3)


PROC 15 indoor

4.6 x10-01 1.5 x10-01 Acute effects CES 2

PROC 15 outdoor

-


3.125

-

PROC 15 indoor


CES 2

PROC 15 outdoor

-


1.88

-

4



• Local emission to air less than 3 kg per day • When the on-site WWTP is used the WWTP sludge should not be spread to soil • Residues may be sent to external waste treatment. • Any measured missions should be ensured to lead to concentrations in the environment which are less than the

relevant PNECs as listed in section 3 above Worker exposure: In order to work within the boundaries of the ES the following conditions should be met:



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above.


Downstream user exposure scenario for Hexafluorosilicic Acid (HFS Acid). Exposure scenario 10: Use of HFS acid in the acidification of minerals. 1

Exposure Scenario 10

Use of HFS acid in the acidification of minerals. Processes Covered: Environmental Releases ERC01: Manufacture of Substances. Worker Processes PROC03: Use in closed batch processes (synthesis or formulation). During the process of mineral acidifcation Hexafluorosilicic Acid is used at dedicated industrial facilities and the associated environmental emissions are extremely limited (almost no emissions) and are generally treated on-site before release to the waste system. Waste acid would primarily be directed to the waste stream and facilities would generally be expected to have dedicated off-gas and effluent treatment facilities. Given that upon contact with water Hexafluorosilicic Acid converts to ions and is fully miscible in water its actual conversion, neutralisation and removal from the waste stream is expected to be extremely rapid and as such removal estimates presented in EUSES below are to be considered conservative. Due to the hazardous and corrosive nature of Hexafluorosilicic Acid the handling systems are highly controlled. Workers are suitably trained and wear appropriate PPE and RPE during the times when very limited (not intended) contact may occur. Contributing Environmental Scenario: Environmental exposure arising due to Mineral acidification use of HFS acid. Contributing Worker Scenarios: Worker exposure arising due to day to day use in closed continuous processes with occasional exposure (such as sampling).. 2.1


Environmental exposure arising due to Mineral acidification use of HFS acid.

Section 2.1 describes the environmental releases that may occur during the mineral acidification use of HFS acid. These releases may occur due to emission to wastewater or through emission to the atmosphere. Atmospheric emissions are monitored and controlled. Liquid wastes would generally be treated (neutralisation to neutral pH and/or precipitation) prior


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to emission to remove any Hexafluorosilicic Acid in the waste water. This process has the effect of lowering of concentration in the industrial WWTP effluent to 7.3 mg/L due to the neutralization and precipitation process to remove Hexafluorosilicic Acid in the waste stream. Reacted HFS acid is precipitated to calcium fluoride and falls to the sludge phase. For the tonnage band considered in this CES this treatment of waste water is not formally required in order to demonstrate safe environmental use however any emissions should be below the 7.3 mg/L level in any case. Sludge from the waste water treatment plant is sent for recovery, incineration or landfill and is not used for agricultural spreading. This precludes any contamination of soil by sludge spreading. Product characteristics


Mineral acidification sites may use up to a largest individual site value of 460 tonnes per annum, with regional amounts of 46,000 per annum assumed the worst case. According manufacturer information the number of emission days per year is 330. Frequency and duration of use

Frequency of use is estimated to be 220 days per year for workers, with a standard 8 hour working day.




Mineral acidification use takes place in highly specialized indoor or outdoor facilities with emissions to air being controlled. Reactions are performed under closed conditions, with transfer pipelines are either fully or partially closed systems. Emission via wastewater is limited by on-site WWTP processes. Mineral acidification processes may be indoor or outdoor. Technical conditions and measures at process level (source) to prevent release

Mineral acidification use is carried out indoors or outdoors in dedicated facilities and losses to surface water or the municipal STP should be prevented by on site WWTP removal. With regards to environmental emissions the loss of fluoride is most relevant as once the HFS acid reacts in the WWTP or with air or environmental moisture fluoride will be formed. Technical onsite conditions and measures to reduce or limit discharges, air emissions and releases to soil

Waste water should be emitted to the on-site WWTP for specialized removal. Emissions to air from mineral acidification use of or from the onsite WWTP should not exceed 80 kg/day. Sludge from the on-site WWTP should not be spread to soil. Any solid waste will be sent as waste for landfill, incineration or off-site treatment. Organizational measures to prevent/limit releases from site




Residues may be sent to external waste treatment, on-site effluent treatment or recycled back into the Mineral acidification use of process. Sludge from the onsite WWTP should be recycled, incinerated or sent to landfill. Conditions and measures related to external recovery of waste

There is no envisaged external recovery of waste. Waste sludge is reduced and then incinerated or sent to landfill and emissions to air are not collected.

2.2

Contributing scenario 2 controlling worker exposure for day to day use in batch or other processes


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with some potential for exposure (such as sampling, cleaning, maintenance)

Worker exposure arising due to day to day use in batch or other processes with some potential for exposure (such as sampling, cleaning, maintenance). Section 2.2 describes the potential exposure to workers during day to day use of mineral acidification machinery, pipelines and storage vessels. Potential exposure may occur during the day to day use however it is more likely to occur during tasks associated with the batch or other processes such as sampling of solutions, cleaning and routine maintenance. Workers involved in acidification of minerals, handling, sampling and transfer of materials are trained in the procedures and protective equipment is intended to cope with the worst case scenario, in order to minimise exposure and risks. This may include chemical resistant clothing and goggles where required. Due to the nature of the materials the level of control is extremely high and so in reality exposure is highly unlikely. Primary emission sources are mostly not located in the breathing zone of the worker. The handling of Hexafluorosilicic Acid is such that contact between product and adjacent air is reduced and controlled loading is used reducing the amount of aerosol formation. The facilities that are housed outdoors are generally not close to buildings and workers are generally located > 4 metres from far field source. It should be noted that though LEV may be in place it is not required to demonstrate safe use and formally only good natural ventilation is required. Product characteristics


Mineral acidification sites may use up to a largest individual site value of 460 tonnes per annum. According manufacturer information the number of emission days per year is 330. Frequency and duration of use exposure

Workers perform standard shifts of 8 hours per day and have standard working years of 220 days per year. Potential for exposure during mineral acidification use of HFS acid is generally considered to be of short duration, with limited potential for exposure. Tasks such as maintenance are carried out only rarely. The effects of exposure to Hexafluorosilicic Acid dermal exposures are likely to be local irritation and corrosivity of the skin. There is no evidence of systemic effects following dermal exposures to Hexafluorosilicic Acid. Estimates of systemic dermal doses associated with acute/short-term and long-term exposures to Hexafluorosilicic Acid were not therefore derived. Furthermore all dermal exposure is ruled out by the exposure limiting methods in place. Human factors not influence by risk management


During the mineral acidification use of HFS acid indoors local exhaust ventilation may be in place but is not formally required. Personal protective equipment is also used to prevent the potential for dermal exposure during the mineral acidification use process. When the processes are carried out outdoors LEV is not required. Technical conditions and measures at process level (source) to prevent release



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Workers are fully trained in safe use of the reactors and associated machinery and the use of appropriate PPE in order to prevent accidental release. Primary emission sources are not located in the breathing zone of the workers. Conditions and measures related to personal protection, hygiene and health.

Workers may potentially be exposed to HFS acid when operating equipment (e.g. valves, pumps or tanks etc) involved in the day to day operations in the day to day use of HFS acid in batch processes with some potential for exposure in activities such as sampling, cleaning and maintenance. All operations are performed in a controlled system. Pipelines and vessels are sealed and insulated where possible. Extract ventilation may be provided at openings and points were emissions may occur. HFS acid is stored in closed containers and tanks and transferred under contained conditions. Submerged loading may be employed for high volume transfer. All technological devices have a proper quality certification, and are regularly controlled and maintained to avoid the uncontrolled discharge of HFS acid. Good occupational hygiene and exposure control measures are implemented to minimise the potential for worker exposure. Workers are well-trained in these procedures and the use of appropriate protective equipment. Workers wear protective clothing (face/eye protection, helmet, anti-acid gloves boots and protective overall). A safety shower is required nearby in case of accidental spillage. 3


A screening-level assessment of inhalation exposure concentrations potentially associated with processes in ES 10 was carried out using the ECETOC TRA model and the parameters shown in the tables below. The tables below show the estimated exposure concentration to Hexafluorosilicic Acid for processes associated with ES 10. The ECETOC TRA model was not considered to give a reasonable screening-level assessment of exposures associated processes involved in ES 10 that are closed and well-controlled and present no real potential for inhalation exposures in workers. As such the unsuitable tier 1 assessment of inhalation exposures associated with ES 10 derived using the ECETOC TRA model were refined using the higher tier inhalation model: the Advanced REACH tool (ART). In the ART model, a mechanistic model of inhalation exposure and expert judgement were used to predict more realistic estimates of inhalation exposure concentrations associated with processes involving Hexafluorosilicic Acid during mineral acidification in ES 10. The Tier 2 assessment was carried out using the parameters and assumptions in the tables below. The predicted 50th and 90th

(worst case) percentile acute/short-term (e.g. exposure over a full-shift) and long-term inhalation exposure concentrations derived using these parameters for processes associated with ES 10 are shown in the tables below. For environmental emissions treatment and significant removal due to precipitation in the on-site WWTP was is expected in practice however it is not required to formally demonstrate safe use for this scenario. Information for contributing scenario 1 (environmental exposure): The following PEC values were calculated using EUSES 2.1


ERC for Compartment:

value unit Sewage (STP effluent) 4.42 mg/L

Sewage sludge 0 mg/kg

Compartments

PEC aquatic (local mg/L) Freshwater (in mg/L) 0.448

Marine water (in mg/L) 0.036


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Compartments PEC aquatic (local) Freshwater sediment (in mg/kg wwt) 0.36

Marine sediment (in mg/kg wwt) 0.036

Compartments PEC (local) Agricultural soil (averaged over 30 days (in mg/kg) 0.04 Groundwater (in mg/L) 0.026

ERC Local

concentration PEC air (local+regional)

Justification

1 Annual average PEC in air, total (mg/m3)

0.0175 0.0175 Estimated using EUSES 2.1.


Compartment PEC mg/L

PNEC mg/L

PEC/PNEC Comments

Tier 2 Freshwater 0.448 0.9 0.533 Safe use demonstrated in tier 2

Compartment PEC mg/kg

PNEC mg/kg

PEC/PNEC Comments

Tier 2 Soil 0.04 11 0.003 Safe use demonstrated in tier 2

Compartments PEC (mg/L) PNEC (mg/L) PEC/PNEC

Tier 2 STP 4.42 51 0.086

Worker exposure

Assessment of dermal risk During the processes that will be carried out for all the exposure scenario for mineral acidification use of Hexafluorosilicic Acid a potential risk may arise if Hexafluorosilicic Acid comes into contact with human skin. This is due to the nature of Hexafluorosilicic Acid and its ability to cause chemical burns. As this effect is considered to be related to the corrosivity of Hexafluorosilicic Acid a threshold DNEL cannot be established for this risk and so measures to control this risk should be assessed in a qualitative manner. This risk is only relevant when workers may come into contact with concentrated Hexafluorosilicic Acid in an industrial or professional setting (as there are no consumer uses). The operational conditions (OCs) and risk management measures (RMMs) used to control and manage the risk of dermal contact events are equally applicable across all the industrial exposure scenarios presented. In the industrial setting an acute risk of dermal burns from exposure to Hexafluorosilicic Acid could potentially exist due to possible splashing of the liquid acid. This risk would be highest at times of transfer to tankers, filling of barrels and filling of small vessels etc. Though these events are considered unlikely due to the extremely high degree of system closure and control the risk is still protected against in order to eliminate any possible routes of exposure. The first aspect of the OCs that reduces the risk of dermal contact is the specialised nature of the systems involved and the degree of closure associated with them. All pipes and transfers lines are closed and sealed in order to reduce any possible


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exposure to leaks or splashes. The reactors themselves are similarly closed and sealed in order to reduce any possible emissions. During times of transfer to/from road tankers gas displacement lines and special connecting systems are utilised in order to reduce the levels of gaseous emissions that could deposit to surfaces including human skin. Specialised tanker coupling/uncoupling systems and targeted purging systems may be employed in certain circumstances where large volumes and high concentrations are required. Training and certification plays an important part in ensuring the workers understand the correct procedures for use of these specialized systems so that the measures in place to reduce emission are not circumvented and so proper function can be maintained. In addition to the measures in place to reduce system emission worker segregation also plays an important part in the reduction of risk in the industrial setting. Workers are generally housed in areas segregated from the main emission sources and time spent on tasks which require close proximity to the emission sources can be minimised effectively. Separate control rooms, screens and outdoor reactor units help to keep workers away from any potential sources of exposure. Emergency measures (and training on procedures and safe work practice) are in place in the industrial setting to ensure that any unforeseen events are safely dealt with in the case that they do arise. These measures would range from procedural policies which are in place to guide workers with respect to proper response in the case of splashes or spills to dedicated equipment (such as emergency showers or spill clean-up kits) which can be used to minimise any effects should unforeseen exposure arise. In order to further protect the worker personal protective equipment (PPE) should be supplied to any personnel who may be working in areas where potential emission sources (such as transfer pipes) are located. Suitable PPE that should be used to prevent dermal contact for workers would be acid resistant clothing, helmets, gloves, goggles and boots. Safety showers should be available in the areas of use in case of accidental spillage. The PPE should be properly maintained and certified and should be replaced when required. These measures combined will effectively function to ensure three aspects of safe use. These are, firstly, reduction of potential emissions with specialised systems. Secondly reduction of the potential for exposure of workers by means such as segregation and training and thirdly physical protection of the worker with the use of correct PPE. With the combination of these measures it is considered that the risk of chemical burns to workers in large scale industrial production and use plants is adequately managed.



Details PROC Parameters/ assumptions Exposure duration 3 480 min Product type 3 Liquid Process temperature 3 Room temperature (15-25oC) Vapour pressure 3 2300 pa Liquid weight fraction 3 Substantial (10-50%) Primary emission source proximity 3 Primary emission source is not located in the breathing zone


Activity class 3 Transfer of liquid products Containment 3 Handling reduces contact between product and adjacent air,

controlled loading 3 Submerged loading Localised controls 3 Vapour recovery systems; LEV Segregation 3 Partial segregation of workers Fugative emission source 3 Not fully enclosed – effective housekeeping practices in place. Dispersion 3 Outdoors or Indoors, any sized room, only good natural

ventilation







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Indoor CES 2 3 Liquid 2.2 x10-01 4.0 x10-01 2.7 x10-01 6.2 x10-01 Outdoor CES 2 3 Liquid 7.2 x10-02 4.8 x10-01 1.7 x10-01 4 x10-01





DNEL (mg/m3)


PROC 3 indoor

7 x10-01 2.2 x10-01 Acute effects CES 2

PROC 3 outdoor

4.8 x10-01


3.125

1.5 x10-01

PROC 3 indoor


CES 2

PROC 3 outdoor

4 x10-01


1.88

2.1 x10-01

4



• Local emission to air less than 80 kg per day • When the on-site WWTP is used the WWTP sludge should not be spread to soil • Emissions from the waste-water stream should be reduced to 7.3 mg/L maximum using fluoride precipitation in the

WWTP. In all cases emissions should be below this value even if on-site WWTP removal is not required. • Residues may be sent to external waste treatment, on-site effluent treatment or recycled back into the mineral

acidification process. • Measured emissions should be ensured to lead to concentrations in the environment which are less than the relevant





above.

safety data sheet - Агрополихим · safety data sheet ... processing aid and in cleaning...

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