Control of Substances Hazardous to Health

(COSHH)

Dr Stephen Ross CChem FRSC, Dip NEBOSH, Grad IOSH, AFOH

Hazardous Substances

• Includes Biological Hazards

• Lead & Asbestos not covered in COSHH as they have their own regulations

Hazardous Substances • Fuel for plant & equipment (oil/petrol / diesel)

– dermatitis, oil acne, cancer

• Cement, plaster – chronic dermatitis

• Solvents, Paints, thinners – Sensitisers, allergic dermatitis, narcotic

• Acids – Burns

• Intermediates and products – Fumes and dust

Biological Hazards

• Weils Disease (Leptospirosis)

• Legionella

• Labs handling live micro - organisms

• Main requirement -Risk assessments (Reg 6) • Then put in place control measures to ensure

people are not exposed to harmful levels of exposure.

Toxicology

Acute Toxicity

• Immediate Effect and often local • You will often be aware of this but not always • Corrosive • Irritant • Narcotic

Chronic Toxicity

• Effects not immediate • by low repeated dose • Often Systemic- not local

Employer must consider the possible enhanced harmful effects of combined or sequential exposures

Where a work activity may expose employees to more than one substance hazardous to health

• Additive 1+1= 2 (xylene + toluene)

• Synergistic 1 + 1 = 10 (ethanol + Carbon tetrachloride) • Potentiation 0+1 =10 (Carbon tetrachloride +

isopropanol)

Other Additive & Potentiation agents

• MEK increases the specific neurotoxicity of

n-hexane and its oxidation products hexan-2-ol, hexan-2-one and hexan-2,5-dione

• peripheral neuropathies • Phosphoric acid and Phenol • Increases dermatitis risk

Take into account all relevant routes of exposure

• Skin absorption/Eye contact • Inhalation • Ingestion • Puncture of the skin

Skin

Waterproof - but not Chemical proof

Skin protection

• Barrier creams – Organic – Water based protection – Limited protection

Gloves

• Need to be the correct size • Need to be the correct type

• Need to be changed regularly- breakthrough

time

• Need to remove them correctly !

Skin Surveillance

• Irritants and skin sensitisers • Don’t just assume it will be hands • Woods dust, epoxy resins, Gylcidyl ethers,

isocyanates, substituted phosphoric acids • Paper based self questionnaire (not sufficient) • Can be responsible person (needs training)

Eye protection

• Glasses

• Goggles

• Face shields

MucoCiliary Escalator

Cardiovascular & Digestive system

• Lungs • Blood • Liver • Kidneys • Bladder

Hierarchy of COSHH assessment (Reg 7)

• Eliminate

• Substitute

• Collective measures first

• Local Exhaust Ventilation (LEV)

• Screening off

• Reduce number of personnel

• Reduce time of exposure

• PPE.

PPE

• Where adequate control of exposure cannot be achieved by other means, provide, in combination with other control measures, suitable personal protective equipment.

Control of Dust & Fumes

-

How far away from the welding torch is the LEV still effective?

At a distance equal to the diameter of the duct the capture velocity is ~10% of hood entry velocity

Should evaluate on tool extraction

Cutting fluid

Inhalation Protection

• DO NOT SMOKE in work area !! • Dichloromethane – Tensor Grip, Anti-spatter,… • Carbon monoxide normal metabolite • Professional DCM paint strippers need HSE approved

training

– Dichloromethane is converted to Phosgene in

cigarette. – The odor detection threshold for phosgene is 0.4

ppm, four times the threshold limit value.

HSG53 67 It is important to know that some pre-existing medical conditions (examples include breathing disorders such as asthma, skin allergies, or even heart problems) may restrict or prevent some workers wearing any RPE, or certain types of RPE. You will need to ensure that workers are fit to wear the selected and required RPE. If unsure, you (the employer) should arrange for appropriate medical assessment.

Lung function- Spirometry

• Asthmagens (Respiratory sensitisers), Toxic by inhalation, cancer, Silicosis, allergic alveolitis.

• Wood dust, Isocyanates, Welding fume, Chrome fume and mist, Respirable crystalline silica, MWF

• RCS chest X-ray after 15 years working and then every 3 yrs thereafter, consider post offer

(Health surveillance for those exposed to respirable crystalline silica (RCS)- HSE)

DIGRESSION

• Tunnelling and other construction work in compressed air

• Pressure above 0.15 bar

Work in Compressed Air Regulations 1996

• barotrauma, - change in surrounding pressure causes direct damage to air-containing cavities in the body directly connected with the surrounding atmosphere e.g. ears, sinuses and lungs;

• decompression illness, - predominantly occurs as a condition involving pain around the joints, or, more rarely, as a serious, potentially life-threatening condition which may affect the central nervous system, the heart or the lungs; and

• dysbaric osteonecrosis, - long-term, chronic condition damaging the long bones, hip or shoulder joints.

• medical surveillance shall be commenced before so assigned.

• at intervals of not more than 12 months

• kept in a suitable form for at least 40 years from the date of the last entry made in it; and

• provided by an appointed doctor

• Specialist medical involving X-rays of long bones. chest • health questionnaire • full clinical examination • spirometry • audiometry • Where work is to take place at 1.0 bar or over, the following should also be

added: – full plate chest radiograph – haematological examination of blood

• at initial and subsequent examinations: – exercise tolerance test – Weight , – Ear, nose and throat – A full plate chest radiograph should be normal

Back to COSHH

Good Industrial Hygiene

• NO FOOD or DRINKS in areas with Chemicals. • Wash hands BEFORE going to the toilet • Wash hands after going to the toilet • Don’t smoke and work with Chemicals…. • Even better … just don’t smoke

– A smoker exposed to asbestos is 50 times more likely to die from the result of the exposure.

Records • (4) Every employer shall keep a suitable record of the examinations and tests carried out

and of repairs carried out as a result of those examinations and tests, and that record or a suitable summary thereof shall be kept available

• for at least 5 years from the date on which it was made. • (5) Every employer shall ensure that PPE, including protective • clothing, is: • (a) properly stored in a well-defined place; • (b) checked at suitable intervals; and • (c) when discovered to be defective, repaired or replaced before further use. • (6) Personal protective equipment which may be contaminated by a substance hazardous to • health shall be removed on leaving the working area and kept apart from uncontaminated • clothing and equipment. • (7) The employer shall ensure that the equipment referred to in paragraph (6) is

subsequently decontaminated and cleaned or, if necessary, destroyed.

Check and review regularly all elements of

control measures for their continuing effectiveness

• Monitoring (Reg 10) • when failure /deterioration of the control measures could result in a

serious health effect, • to be sure that a WEL is not exceeded • as an additional check on the effectiveness of any control measure • always in the case of the substances or processes specified in Schedule 5; • when any change occurs in the conditions affecting employees’ exposure

which could mean that adequate control of exposure is no longer being maintained,

• Where risk assessment determines it to be necessary

Measuring Exposure Snatch sample only not

suitable for personal monitoring

Biological monitoring useful as it measures exposure by all routes e.g. isocyanates, Chrome VI, Butanone, DCM (HSG167/EH40)

know your limits!

WEL’s STEL

Introduced 2004

Compound ppm mg/m3 ppm mg/m3 Styrene 100 430 250 1080

Styrene • Ototoxic • At 87 - 139 ppm

vestibule-ocular motor system disorders can occur and also colour vision dysfunction with the latter being reversible several weeks after the end of exposure.

GESTIS

Health Surveillance Reg 11 Where:- a) the employee is exposed to one of the substances or processes specified in COSHH Schedule 6 and there is a reasonable likelihood that an identifiable disease or adverse health effect will result from that exposure; or (b) the exposure is such that – • an identifiable disease or adverse health effect, • reasonable likelihood that the disease or effect may occur AND • there are valid techniques for detecting indications of the disease or effect • And the technique is of low risk to employee Examples • Blood/urine samples- Biological Monitoring • Spirometry • Skin surveys • Audiometry

Health Surveillance

• Skin surveys : skin sensitisers and irritants • Lung Function: Asthmagens, • Nasal Checks: Chrome VI electro plating • Colour Vison : Styrene (if good control is not

in place) • Audiometry – Ototoxic agents • X-ray- RSC, Compressed air environments