omar khalid oh presentation march 2015 1.0 khalid oh... · 2018. 5. 28. · microsoft powerpoint -...

Occupational Hygiene

Omar Khalid CMIOSH LFOH

25 March 2015

What is Occupational Hygiene?

BOHS definition…

© 2015, Mabbett & Associates Ltd Ref: BOHS

When might you need to consider Occupational Hygiene?

© 2015, Mabbett & Associates Ltd

Chemical Hazards.


Physical Hazards.




Ergonomic Hazards.



Biological Hazards.

Occupational Hygiene

For the purpose of today’s session, let’s justconsider chemical hazards…


Substances Hazardous To Health

COSHH Regulations 2002 /COSHH Regulations (NI) 2003define substances hazardous tohealth under 5 broad categories.

L5, 6th edition, 2013.


Other Regulations

Separate regulations are in place regarding lead

and asbestos, but these substances are also

considered under occupational hygiene.


Routes of Exposure


COSHH Regulations

� Assessment.

� Prevention or control.

� Use of controls.

� Maintenance, examination and testing.

� Monitoring (Regulation 10).

� Health surveillance.

� Information, instruction and testing.


Regulation 10

Regulation 10 of COSHH deals with monitoring exposures inthe workplace and indicates this to be requisite duringconditions including where:

� failure or deterioration in a control measure could resultin a serious health effect.

� measurement is needed to be sure that an WorkplaceExposure Limit (WEL) is not exceeded.

� it is necessary to check the effectiveness of any controlmeasures in place.


Monitoring Exposure


Regulation 10

� Monitor using suitable techniques to assess employees’exposures to hazardous substances via all routes -inhalation, ingestion and/or skin.

� When considering air quality, exposure by inhalation ismost likely.

� Employees’ exposures by inhalation to substanceshazardous to health is measured by monitoring the air inthe employee’s breathing zone.


Workplace Exposure Limits (WELs)

� Regulatory requirement not toexceed WELs.

� Reduce exposure to certainsubstances as far as isreasonably practicable.

� An occupational hygienist’sreport should make referenceto EH40.

EH40, 2nd edition, 2011.


Workplace Exposure Limits (WELs)

� Long-term over 8-hour Time-Weighted Average (TWA)reference period.

and/or

� Short-term (STEL) over a 15-minute period.

� May not protect highly susceptible personnel.

� Uncertainty for carcinogens/sensitisers.

� Where there is no WEL for a substance, don’t assume it’ssafe to use.


Types of Airborne Substances

Type Definition Example

Dust Solid particles suspended in air

-total inhalable dust is fraction of

dust which may enter

nose/mouth

- respirable dust is small enough

to penetrate the gas exchange

region of the lung

Wood dust

Respirable crystalline silica

Fume Solid particles formed by

condensation from the gaseous

state

Welding fume

Mist Liquid droplets suspended in air Oil mist

Vapour Gas/liquid droplets from

substances which are normally

solid or liquid

Solvent vapour


Dust Size Fractions


Types of Airborne Substances

Type Definition Example

Gas Substance with nodefinite volume or shapewhich will expand to fillany container

Carbon dioxide

Aerosol Airborne liquid or solidparticles which are smallenough to float in air

CFC’s

Smoke Incomplete combustionproducts of organic origin

Wood smoke

Fibres Solid particles normallyof a length to diameterration of >3:1

Machine-mademineral fibre (MMMF)e.g. glass wool


Dust Fume



Chemical Hazards - Health Effects

INHALATION of dusts and fumes can cause:

� Respiratory irritation: glass fibre dusts

� Lung disease: silica dusts

� Respiratory sensitisation: solder fume

� Systemic poisoning: lead oxide fume

� Cancers: asbestos


Chemical Hazards - Health Effects

INHALATION of gases and vapours can cause:

� Asphyxiation: nitrogen

� Chemical asphyxiation: carbon monoxide

� Respiratory irritation: ammonia

� Lung damage: chlorine

� Narcotic effects: paint solvents


Occupational Hygiene Monitoring

So, if you do need to carry out exposure

monitoring, what do you do?

� Internet search?

� HSG173 Monitoring strategies for

toxic substances?

� Look up the BOHS Directory of

Occupational Hygiene Services?HSG173, 2nd edition,

2006.



So, if you do need to carry out exposure

monitoring, what do you do?

� Internet search?

� HSG173 Monitoring strategies for

toxic substances?

� Look up the BOHS Directory of

Occupational Hygiene Services?

HSG173, 2nd edition, 2006.


Investigative/Basic Approach

� direct readout meters for airborne particulate matter and for

gases such as CO, CO2, O3, CH4, VOCs.

� direct reading stain tubes, e.g. Draeger, Kitagawa.

� sample bags, e.g. Tedlar for collection of sample of gas

and laboratory analysis.



Investigative/Basic Approach

Pros

� Relatively simple to use.

� Short-term (grab) sampling with immediate results in most

cases.

Cons

� Indicative levels only, sometimes with large margins in

detection.

� In most cases, cannot be compared directly with WELs.



Detailed Approach - Compliance Testing

A more detailed approach is most commonly required to assessexposures to airborne substances. The nature and extent of themonitoring programme adopted will depend upon variables, including:

� nature of hazard(s).

� number of personnel who may be affected.

� range of tasks carried out.

� similarity of working environment and control measures.

� findings from any initial appraisal and/or basic survey.

� other factors which may affect exposure (e.g. draughts) or risk of harm(e.g. pregnancy).



� Two types of monitoring:

o Personal monitoring.

o Area (static) monitoring.

� Monitor for representative periods of time.

� Use suitable sampling, analytical and quantification

procedures.


Techniques

� U.K.: Health & Safety Executive (HSE)

- Methods for the Determination of Hazardous

Substances (MDHS)

http://www.hse.gov.uk/pubns/mdhs/

� USA: National Institute for Occupational Safety and Health

(NIOSH) and Occupational Safety and Health

Administration (OSHA)

� Research documents.


Equipment

Air monitoring involves pumped sampling. Generally,equipment for this consists of:

� sampling pump;

� tubing, and

� collecting medium.


Equipment

Sample collection media includes:

� Pre-weighed filters and foam inserts for dusts.

� Glass sorbent tubes for gases and vapours.

� Impingers containing solution for vapours.


IOM Head for Total

Inhalable

Dust

Cyclone Head for

Respirable

Dust Sorbent Tubes

Personal Monitoring


Ref: SKC Ltd

Personal Monitoring - Questions


Ref: SKC Ltd

� Does this give off radiation?

� Am I being recorded?

� Can I go for a smoke?

� Can I go to the toilet?

� Will I get told the results?


To summarise, for air monitoring, the OccupationalHygienist will:

� identify the substances for which monitoring is to becarried out.

� develop a monitoring strategy making reference torelevant MDHS (or similar).

� carry out personal (and static) monitoring usingappropriate media.


Case Study 1

� Manufacturer of air conditioning units.

� All processes carried out in-house - from sheet metalin, to final electrical testing.

� Processes include metal cutting, brazing, powdercoating and assembly. Also welding duringmaintenance activities.

� Monitoring last carried out over 5 years ago.

� New processes and equipment introduced sincethen.


Case Study 1 (Cont’d)

Air monitoring for:

� Total inhalable andrespirable dusts at paintplant.

� Dusts, metals (Cu, Ag) andmethanol during brazing.

� Mineral oil mist at presses.


Xxxx

Case Study 2

� Food premise – making pizzas to supply takeaways.

� Unannounced inspection by HSE.

� Identified no assessment of exposures to flour dust (arespiratory sensitiser).

� No reported cases of asthma.


Case Study 2 (Cont’d)

Air monitoring for flour dust during

different activities, including:

� Dough preparation.

� Cleaning.© 2015, Mabbett & Associates Ltd

Occupational Hygiene Monitoring - Results

� Following monitoring, samples are sent to a laboratory for

analysis.

� For quality purposes, use UKAS accredited laboratories,where possible.

� Laboratory will provide table(s) of results.

� The occupational hygienist will then calculate individuals’measured exposures to the airborne substances forcomparison with relevant WELs / occupational exposurelimits.


Occupational Hygiene Monitoring - Results


Required Reporting


� The report submitted by the occupational hygienist shouldinclude:

� BOHS ‘Clear and concise report writing: guidance foroccupational hygienists’.

o Premises.o Workplace.o Worker activity.o Product.o Chemical agent.

o Exposure modifiers.o Measurement

strategy.o Measuring procedure.o Results.o References.

Remember Adequacy of Control

Schedule 2A of COSHH Regulations -

Principles of good practice for the control of

exposure to substances hazardous to health


Monitoring Review

� Monitoring should take place at regular intervals.

� No definition of “regular”, but consider factors,

including:

o exposures previously exceeding WELs;

o equipment/process changes or improvements,

and

o accidents/reports of ill-health.


Other Types of Monitoring

� Wipe sampling of the skin - can provide useful informationon the spread of substances and the potential forexposure.

� Biological monitoring - the measurement of a substanceor its metabolite in a biological fluid (breath, urine orblood).

� Biological effect monitoring - used to describe the

measurement of non-harmful, often reversible, biologicaleffects in a worker following exposure, e.g. pesticideexposure can affect certain enzyme activity.


Biological Monitoring Guidance Values (BMGVs)

� Biological monitoring can be a very useful complementary

technique to air monitoring when air sampling techniquesalone may not give a reliable indication of exposure.

� Measurements reflect absorption of a substance by allroutes.

� BMGVs are non-statutory and any biological monitoringundertaken needs to be conducted on a voluntary basis.

� Certain BMGVs listed in Table 2 in EH40.


Health Surveillance

� Examples of types of health surveillance include:

o Spirometry (lung function) test.

o Skin surveillance checks.

o Audiometric (hearing) test.

o Hand-arm vibration questionnaires.

� Health surveillance must be conducted by occupationalhealth practitioners (who may not be occupationalhygienists).


Health Surveillance

� Records of health surveillance containing individuals’

details are required to be kept for at least 40 years fromdate of last entry.

� Employees are entitled to view their personal records, onrequest.

� Health surveillance records must be shown to the HSENI,on request, and forwarded to the Executive should abusiness cease trading.


Occupational Health

Thank you for listening!

Can you relate to the issues discussed?

Questions or comments welcome


omar khalid oh presentation march 2015 1.0 khalid oh... · 2018. 5. 28. · microsoft powerpoint -...

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