UTC Environment, Health & Safety group

EH&S European Regional Conference

18 – 20 October, 2016

Amsterdam, Netherlands.

Industrial hygiene in the workplace

current topics of interest

Sean Mahar, PhD, CIH, CSP, PE

Euro Safety and Health

sean@eurosh.com

1

Industrial hygiene in the workplace – current topics

of interest

Sean Mahar, PhD, CIH, CSP, PE

Euro Safety and Health

Contact Details

Sean Mahar

Euro Safety and Healthsean@eurosh.com

www.eurosh.com

UK Phone: 44 (1743) 362 076UK Mobile: 44 747 6605 710

Introduction

• The industrial hygiene (IH) program has several facets and chemicals and noise are the usual suspects but the recent introduction of the Physical Agents (Electromagnetic Fields) Directive has increased interest in this often overlooked topic.

Educational Objectives

• This presentation is intended to act as an introduction to better understand the common chemical, noise and EMF risks in UTC workspaces and the techniques to evaluate them to maximize the value of IH consultants.

The Plan

• Industrial hygiene and its role

• Common issues at UTC sites– Metalworking fluids

– Modern solvents

– Chromium

– Ventilation

• The EMF Directive

2

Industrial Hygiene

“the recognition,

evaluation,

and control

of hazards from work that may result in injury, illness, or affect the well being of workers.“

Assessments

• Qualitative evaluations primarily addresshazard

• Quantitative evaluations primarily addressrisk

Hazards

• Chemical– Solvents, dusts, acids, metals, etc.

• Physical– Noise, vibration, lighting, electromagnetic

radiation, ergonomics

• Biological– Animals and by products, mold, endotoxins

Hazard and Risk

• Hazard is the potential to cause harm

• Risk is the likelihood of harm occurring

Routes of Entry

• Inhalation • Ingestion • SkinInhalation particularly important exposure important due to lung surface area

Occupational Exposure Limits (OELs)

• A concentration in parts per million (ppm) or in milligrams or micrograms per cubic meter of air (mg/m3 or µg/m3).

• Not safe/unsafe limits but aimed at protecting most workers.

• Some people could still be affected.

3

OELs

• Short-term limits can be 15 or 20 minute average or a ceiling level

– substances that can cause their effect in a short time, such as irritants, or for substances that can have very serious effects.

• Long term limits usually an 8 hour average– normally substances that exert a long term or

cumulative effect

OEL Sources

• European Union - Indicative Occupational Exposure Values (IOELVs)

• UK Workplace Exposure Limits (WELs)• US Occupational Health and Safety

Administration (OSHA) - Permissible Exposure Limits (PELs)

• American Conference of Governmental Industrial Hygienists (ACGIH) - Threshold Limit Values (TLVs®)

Other OELs

• American Industrial Hygiene Association (AIHA) – Workplace Environmental Exposure Levels (WEELs)

• Bundesministerium für Arbeit (BMA) Maximale Arbeitsplatzkonzentration(MAKs)

• NIOSH Recommended Exposure Limits (RELs)

Metalworking Fluids

• Evolved over time to current water based fluids

• Dermatitis traditionally a concern• Some machinists suffer from airways

sensitization with asthma or alveolitis• Microbial growth and byproducts such as

endotoxins thought to be culprit• NIOSH REL 0.5 mg/m3

Ventilation

HEPA filter stops particulates

Delay in opening allows mist to clear

Machine mix

4

A Puzzle

• A sticky amber film forming on vertical surfaces, most notable on stainless steel fridges and wire grids

• Sample scrapings sent to 2 labs for analysis who both identified it as MDEA, n-methyldiethanolamine

MDEA

• n-methyldiethanolamine

• CAS 105-59-9

• Water soluble

• BP, 760 mm Hg, 247.3 C

• VP, 20 C, <0.01 mm Hg

• R36 Irritating to eyes

Metalworking Fluid

40%

Another Fluid

MBM

• n,n'-dimorpholinomethane• CAS 5625-90-1• Water soluble• BP, 760 mm Hg, 266.4 C• VP, 20 C, <0.01 mm Hg• H314: Causes severe skin burns and eye damage• H317: May cause an allergic skin reaction• H350: May cause cancer• H341: Suspected of causing genetic defects

Modern Solvents

• In the old days we had benzene– With cancer concerns

• Then trike– With ozone depletion concerns

– Also with cancer concerns

• Now a revolving door of substitutes

5

n-Propyl Bromide

• 1-bromopropane

• n-PB

• CAS 106-94-5

• Degreaser and cleaner– Swansolv

– Ensolv

n-Propyl Bromide

• American Conference of Governmental Industrial Hygienists (ACGIH) -Threshold Limit Value (TLV®)

• 10 parts per million (ppm) in 2003 • 0.1 ppm in 2014• irritation and nervous system damage

n-Propyl Bromide

Largely being replaced bytrans-1,2-Dichloroethylene

trans-1,2-Dichloroethylene

• trans DCE

• t-DCE

• CAS 540-59-0

• Degreaser and cleaner– Novec™

– Vertrel™ C-HD

trans-1,2-Dichloroethylene

• USA, UK, Germany have 200 ppm limits

• irritation eyes, respiratory system; central nervous system depression

Chromium

6

Chromium

Exists in different oxidation states:

0 (elemental metal, Cr),

+3 (trivalent, CrIII) , and

+6 (hexavalent, CrIV)

Elemental and trivalent have a TLV of 0.5 mg/m3 (500 µg/m3) due to respiratory and skin irritation, dermatitis concerns

Chromium (VI)

Hexavalent Chromium is also a carcinogen

the TLV is 50 µg/m3, for soluble compounds like sodium chromate (chromic acid)

the TLV is 10 µg/m3, for insoluble compounds like barium chromate

the TLV is 0.5 µg/m3, for strontium chromate

Local Exhaust Ventilation (LEV)

Fan Air cleaner Hood

Stack

Air Flow

Air FlowDuct

Paint Booth Problems

Inadequate flow:

ACGIH Ventilation Manual (good practice) recommends 0.5 m/s

Bad design:

Flow in booth causes dead spots and counter currents

Protective Flow Protective Flow

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Useless Flow

0.5 m/s

Poor Evaluation

0.5 m/s here, not here

Physical Agents Directives

• Vibration 2002/44/EC• Noise 2003/10/EC• Artificial Optical Radiation 2006/25/EC• Electromagnetic Fields 2013/35/EU

Electromagnetic Fields Directive

Addresses:

• Direct effects

• Indirect effect

Does not address long-term effects

Directive at risk workers

• with active implanted medical devices (AIMD)

• with passive implanted medical devices containing metal

• with body-worn medical devices

• Pregnant workers

Electromagnetic Fields Directive

Requires:

• Risk assessment

Sets:

• Exposure Limit Values ELVs

• Exposure Action Values EAVs

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Electromagnetic Fields Directive

Risk Assessment can drive:

• Worker information instruction and training

• Controls

• Medical surveillance

EMF Risk Assessment

• Identify possible sources

• Check manufacturer data

• Measure if needed

• Model if needed

• Implement controls if needed

Electromagnetic Spectrum EMF Sources

Low Frequency– Electric welding and melting

– High current or voltage (>500A, >200 kV)

– Induction heaters

– Magnetisers/demagnetisers

– Electric crack detection

EMF Sources

High Frequency– Communications antennas

– Industrial heating and drying

– RF plasma (chem vapor deposition, sputtering)

– RF welding

EMF Hazards

Effects vary depending on field

• High frequency fields

• Low Frequency fields

• Static fields

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High Frequency (100 kHz – 300 GHz)

• Tissue heating• Specific energy Absorption Rate (SAR)

– 100 kHz-10 MHz limb heating, induced E

– 10 MHz-400 MHz whole-body heating

– 400 MHz-10 GHz: localized heating

– 10 GHz-300 GHz: surface heating

Low Frequency (1 Hz – 100 kHz)

• Electric fields cause surface charge:– induction of current density and electric fields

within body

• Magnetic fields penetrate body:– induction of current density and electric within

body

• Adverse health effects:– Cognitive impairment, nerve stimulation

Static Fields

• Electric fields– Electrostatic discharge to grounded objects

• Magnetic fields Movement in a static field– Vertigo, Nausea, Metallic taste

– Magneto-phosphenes (flashes before eyes)

• Problems with metallic implants, projectiles, medical devices

Hierarchy of Control

PPE

Administer

Engineer

Substitute

Eliminate

EMF Controls

• Change equipment or process

• Shielding, interlocks

• Barriers, signage

• Personal protection– clothing, meters and alarms

10

Wave Parameters

• Wavelength

• Frequency

• Velocity

Wavelength

• Distance

– Peak to peak

– Trough to trough

• Units

– Meters

– (km to nm)

• Symbol is “ λλλλ”

Frequency

• Periodicity

– Cycle completion

• Units

– Cycles/second

– Herz (Hz)

• Symbol is “f”

Velocity

• Speed of Light

• 3 x 108 m/s

• Symbol is “c”

– sometimes “ νννν”

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Relationship

λλλλ = c/f

λλλλ = wavelength (m)

f = frequency (Hz)

c = velocity (m/s)

Voltage

• Electrical pressure

• Potential to do work

• Volts

Current

• Movement of charge

• Amperes

Electric Fields

• Produced by Voltage

• Volts/meter

• Symbol is “E”

Magnetic Fields

• Produced by current

• Amps/meter

• Symbol is “H”

E and H

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E and H relate

• Free space impedance

• E/H = 377ΩΩΩΩ

Power density

HEPDrr

×=PD = Power density (mWatts/cm 2)

E = Electric Field (volts/meter)

H = Magnetic Field (amps/meter)

www.narda- sts.com

Inverse Square Law Inverse square law2

2

112

=dd

II

I = incident energy

d = distance

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Measurement

• Electric Field• Magnetic Field• SAR

www.narda-sts.com

E or H Measurement

Pickup

Detector

Readout

Electric Field Measurement

• Pickup–small antenna

or dipole

• Detector–diode or

thermal sensor

Magnetic Field Measurement

• Pickup–small loop or

dipole

• Detector–diode or

thermal sensor

14

LF Measurement

• ETM-1 Meter for Static Magnetic Fields

• Measurement range: 0 Hz, up to 2 Tesla

• Properties: For magnetic field, with isotropic Hall probe, automatic and manual selection of measurement range

www.narda-sts.com

HF Measurement

• EMR-200 / EMR-300 High-frequency radiation meters

• High-frequency Survey System with interchangeable E and H field probes

www.narda-sts.com

www.narda-sts.com

Specific Absorption Rate (SAR)

• Time rate of energy absorbed in an incremental mass, divided by that mass.

• Average SAR in a body is the time rate of the total energy absorbed divided by the total mass of the body.

• watts per kilogram (W/kg)

SAR Measurement

• measure the E-field inside the body

• measure temperature change

• use differential power method