Unit 2_Overview of Industrial Hygiene

Diploma in OSH – Kolej Fajar, Miri

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Lecturer: Tay Kay Chuang (Msc. in OSH, USA)

Learning Objectives

� State the definition of Occupational Hygiene

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� State the roles of responsibilities of Industrial Hygiene practitioners

� Explain the principles of Occupational Hygiene

Definition of Occupational / Industrial Hygiene

� Definition 1 (International Occupational

Hygiene Association By-laws – IOHA)

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“ Occupational Hygiene is the discipline of

anticipating, recognizing, evaluating and controlling

health hazards in the working environment with the

objective of protecting worker health and well-being

and safeguarding the community at large.”

http://www.ioha.net/

Definition of Industrial Hygiene

� Definition 2 (American Industrial Hygiene Association - AIHA)

“That science and art devoted to the anticipation,

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“That science and art devoted to the anticipation, recognition, evaluation, and control of those environmental factors and stresses arising in or from the workplace, which may cause sickness, impaired health and well-being, or significant discomfort among workers or among citizens of the community”

http://www.aiha.org/Content

Definitions – Industrial Hygiene

IOHA AIHA

Occupational Hygiene is the discipline of anticipating,

Industrial Hygiene is “That

science and art devoted to the

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discipline of anticipating, recognizing, evaluating and controlling health hazards in the working environment with the objective of protectingworker health and well-being and safeguarding the community at large.”

science and art devoted to the anticipation, recognition, evaluation, and control of those environmental

factors and stresses arising in or from the workplace, which may cause sickness, impaired health and well-being, or significant discomfort among workers or among citizens of the community”

PREVENTION OF EXPOSURE

INDUSTRIAL HYGIENIST

TREATMENT

OCCUPATIONAL

HEALTH DOCTOR

DISEASE

WORKERS

HAZARDS

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Qualification of an Industrial Hygienist

� A person having a college or university degree (s)

in engineering, chemistry, physics, medicine or

related physical and biological sciences, who has

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related physical and biological sciences, who has

also received specialised training in recognition,

evaluation, and control of workplace stressors and

therefore achieved competence in industrial

hygiene.

What is the difference between Industrial hygiene and Occupational hygiene?

� None really.

� The term Industrial Hygiene originated in the USA

while in other parts of the world it is known as

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while in other parts of the world it is known as

Occupational Hygiene.

� In some ways the term Occupational is a better

description as health risks occur in all places that

people work such as offices, shops, hospitals and

farms, not just in places you would think of as

industrial.

1. Anticipation of potential health risks

2. Recognition of existing health hazards at

Basic Principles of Industrial Hygiene

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2. Recognition of existing health hazards at

the workplace

3. Evaluation of health risks

4. Control of unacceptable risks

Remember the acronym: A.R.E.C.

1. Anticipation of potential risks

� Best done –

� in the design stage of a process or equipment or

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� at the formulation stage of a new substance or

chemical

Advantage: Eliminate the need for review or

redesigning, thus save high costs.

1. Anticipation of potential risks

� Basic information to consider:� Characteristics of the process or equipment

� Physical and chemical properties of the formulation

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� Adverse health effects from past experience and reported cases of occupational diseases and poisoning

� The process of anticipation is not easy and requires vast experience. Need to engage the assistance of experts such as the industrial hygiene practitioner, toxicologist and occupational health doctor.

Characteristics of Process or Equipment

Process Structure

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Concept of a Job Shop – a machine shop

Job Shop

• Flexible operation that may involve several

work activities to complete the job.

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work activities to complete the job.

• Uses general purpose equipment.

• Relies on the knowledge of workers to

produce a variety of products.

Work Activity 1 – Use of a Drill Press

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Work Activity 2 – Use of a Lathe

A lathe is machine toolused for cutting, sanding,

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used for cutting, sanding, knurling, drilling, or deformation of a work-piece to create an object of the desired shape.

Gang Milling

Work Activity 3

Use of a Milling Machine

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Angular Milling

Work Activity 3

Use of a Milling Machine

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Straddle Milling

2. Recognition of Health Hazards

� This may be achieved through –a. Workplace inspection

i. Look at workplace environment, work processes,

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i. Look at workplace environment, work processes, types of materials & equipment used;

ii. Observe workers at work

2. Recognition of Health Hazards

b. Health surveillance and area monitoring

c. Workers health records

Annual Hearing Test

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c. Workers health records

Area Toxic Gas Monitoring

2. Recognition of Health Hazards

d. Review of past Incident investigation reports.

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e. Discussion with the management and workers

2.1.Harmful Factors that exist at the Workplace

� Many workers may be exposed to a number of health hazards at work.

Hazard recognition :

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� Hazard recognition :

– Identifying factors or work processes that may be harmful to

health.

– Knowledge of the physicochemical properties of a material/

substance, its harmful effects to health and identification

techniques are essential. (Refer to relevant Chemical Safety Data

Sheets)

2.1. Health Hazards encountered at Work

1. Chemical Substances

2. Physical agents.

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2. Physical agents.

3. Biological agents

4. Ergonomics

5. Psychological factors.

2.1.1. Chemical Hazards

� Hazards – risks are associated with the use of chemicals.

� Hazardous chemicals may cause –

� Fire & Explosion Forms of Chemicals

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� Adverse health effects

� Damage to the environment

Forms of Chemicals

• Dust,

• Particles and smoke

• Liquid and mists

• Gas and vapour

Common Types

1. Solvents

2. Metals

3. Acids and Bases

4. Pesticides

2.1.2. Physical Hazards

Excessive exposure to the following physical hazards may cause harm to our health –

� Noise� Vibration

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� Vibration� Ionising radiation

� Cosmic rays – gamma, alpha, Beta and X-rays;

� soil/rock radioactive elements– uranium, thorium, radium, potassium-40;

� Man-made nuclear radiation

� Non-ionising radiation� UV, Infrared, microwave, laser.

� Lighting� Extremely high/low temperature� Extremely high/low air pressure

2.1.3. Biological Hazards

� Micro organisms

– Bacteria, viruses and Parasites.

– The virus of contagious diseases may spread through its vectors.

� Toxins (spider, snake, scorpion, jellyfish, wasp)

� Plants (fungi, yeast, cotton dusts)

Bacteria Anthrax, legionnaire’s disease, botulism, E.Coli, Bacteria Anthrax, legionnaire’s disease, botulism, E.Coli,

salmonella

Viruses H5N1(Avian Flu), SARS, HIV, mumps, Dengue fever.

Hepatitis A/B/C , Variecella (chickenpox)

Fungi Poisonous mushrooms

- Amanita virosa (Destroying Angel),

– Amanita phalloides (Death Cap)

Parasites Malaria, mites, leeches, intestinal worms

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2.1.4. Ergonomic Hazards

Musculoskeletal disorders affecting workers may

arise from unsuitable work conditions or physical incapacityto carry out their assigned tasks.

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1. Awkward body postures

2.1.4. Ergonomic HazardsExamples of unsuitable work conditions or physical incapacity:

2. Manual lifting of heavy loads

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3. Repetitive hand Movements

2.1.4. Ergonomic Hazards

Examples of unsuitable work conditions or physical incapacity:

4. Cramp work space. 5. Poor lighting

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2.1.5. Psychological hazards

Tensions at the workplace may disturb the

concentration and mental health of the worker

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Examples of Tensions at the workplace

� Monotonous work

� Excessive workload and overtime

� Poor work relationships with colleagues and supervisors

� Shift work

� Remuneration and annual leave issues

� Sexual Harassment

2.2. Workplace Inspection

Key considerations:

1. Inspection team members be knowledgeable on the processand well versed in the aspects of worker safety and health.

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2. Inspection to be coordinated by a line supervisor.

3. Purpose of inspection - clearly defined and communicated to each group member.

4. Method of inspection - agreed

5. All follow-up actions must be recorded and monitored.

6. Those at risk must be briefed on the actions that need to be taken.

2.2.1 Approaches in Workplace Observation

� Geographical approach

– By location or work division

– Suitable to simple processes / various processes in the

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– Suitable to simple processes / various processes in the same location

� Hazard tracking

– Track specific hazards such as noise

– Used to evaluate compliance to specific Regulations.

� Process flow

– By following the work activity or process

– Suitable for complex work processes

� Identify all health hazards

– From both planned and unplanned activities

Communication with operators or workers

2.2.2. Workplace Observation

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� Communication with operators or workers

who handle the process or control the

equipment

� Measurement of hazard using equipment

– Direct reading equipment

� Ask about symptoms/discomfort

– Example

Headache, skin irritation, vomiting

2.3. Employee Feedback

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– Headache, skin irritation, vomiting

� Look into complaints

– Example

– No provision of Personal Protective Equipment

2.4. Medical Records

� Poisoning cases and work related diseases

� Employee health complaints

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� Health surveillance and occupational health

programs

� To determine the level of worker exposure

(high, medium or low) to health hazards and the

effectiveness of the existing control measures,

3. Objectives of Risk Evaluation (Assessment)

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effectiveness of the existing control measures,

and their relationship to the risk of disease.

� To enable decisions to be made on additional

control measures to bring the health risks down

to within PEL (Permissible Exposure Limit).

– e.g. engineering control to reduce airborne contaminants, worker training, health surveillance.

3.2. Risk Evaluation – what to look at?

3.2.1. Risk = Hazard x Exposure

Hazard Component= Magnitude of hazard and the potential adverse health effects from

possible routes of entry or contact.

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= Magnitude of hazard and the potential adverse health effects from possible routes of entry or contact.

Exposure Component= Chances of overexposure occurring by taking into account:

i. Characteristics of exposureii. Level of exposure

3.2.2. Risk Conclusion – takes into account the work practices and personal factors including individual susceptibility.

3.2.1. (i) Characteristics of exposure� Who are exposed (based on Job types and tasks

3.2. Risk Evaluation

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� Who are exposed (based on Job types and tasks performed)?

� How many are exposed?

� What are they exposed to? ( 5 groups of health hazards)

� How are they exposed?� Inhalation

� Skin Absorption

� Ingestion

� Injection

3.2.1. (ii) Level of Exposure� Frequency of exposure

– daily, weekly, monthly?

3.2. Risk Evaluation

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– daily, weekly, monthly?

� Duration of exposure

– by seconds, minutes, hours?

� Intensity of exposure

– high, medium, low?

3.2.1. (ii) Level of Exposure

– Exposure intensity - Quantitative

� Using equipment to measure the

3.2. Risk Evaluation

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� Using equipment to measure the intensity or magnitude of exposure

– Exposure intensity - Qualitative

� Using observation and professional opinion

Field Sling Psychrometer

1. Chemical Substances

Consider the following factors when evaluating the risk of exposure

to chemicals hazardous to health:

Examples of Risk Evaluation

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to chemicals hazardous to health:

a) Work methods and practices

b) Work environment

c) Personal hygiene

1. Chemical Substances

a) Work methods and practices

Observe each task to find out –

Examples of Risk Evaluation

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Observe each task to find out –

i. How chemical is being handled?

ii. Any chemical spillage?

iii. The use and maintenance of personal

protective equipment

iv. Any damage to skin or protective gear?

v. Duration of exposure to chemical

1. Chemical Substances

b) Work Environmenti. Is the air being contaminated by chemical vapor, mist, dust or

fume?

Examples of Risk Evaluation

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fume?

ii. Any presence of pollutants on work surfaces?

iii. Any obvious smell? (Caution! Using senses to smell for chemical odor is recommended.)

c) Personal Hygienei. Is PPE used clean before use?

ii. Has the worker washed hands with soap and water before taking drinks or meals?

iii. Has worker showered at the workplace or at home, and changed out the contaminated clothes with new, clean ones (including the under garments)?

3.2.2. Risk Conclusion

� Risk conclusion is made after taking into account -

i. Level of risk exposure (high, medium or low) based on

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i. Level of risk exposure (high, medium or low) based on qualitative or quantitative assessment and rated against the Industry accepted Permissible Exposure Limits.

ii. The work practices, and personal factors (including individual susceptibility)

ii. The adequacy of existing control measures

� Levels of controls for exposure exceeding the

permissible limits need to be monitored to

ensure the protection of workers’ health.

Occupational Exposure Standards

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ensure the protection of workers’ health.

� Permissible Exposure Limits (PEL)- Malaysia

� Threshold Limit Value (TLV) - ACGIH

� Workplace Exposure Standard (WES) – UK &

Australia

Permissible Exposure Limits (PEL) under FMA 1967 (values in brackets – USECHH Reg2000)

� LEAD : 0.15 mg/meter3 (0.05mg/m3 )

� ASBESTOS : 1 fibre/millilitre air (0.1 fibre/ml of air)

� NOISE

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� NOISE

– 90 dBA for 8 hours; 115dBA maximum

– 140 dB for impulse noise

� MINERAL DUST:

– 5 mg/m3 for respirable dust (3mg/m3 );

– 10 mg/m3 for total dust

– 0.1 mg/m3 for respirable quartz

� CEILING LIMIT

– May not be exceeded at any time

8-HOUR TIME WEIGHTED AVERAGE (8-hour TWA)

Permissible Exposure Limits under OSHA 1994(Malaysia)

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� 8-HOUR TIME WEIGHTED AVERAGE (8-hour TWA)

– May not be exceeded after average for a duration of 8 hours

� MAXIMUM EXPOSURE LIMIT (15 MINUTE AVERAGE)

– May not be exceeded at any 15 minute average

– The value is three times the 8-hour TWA

Principle of Risk Control

� Prioritise the control measures at the source, not the worker

Prioritise the elimination of hazards, not the

4. Control of Health Risks

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� Prioritise the elimination of hazards, not the reduction of exposure

� Controls should target below the permissible exposure limits

� Controls should be as low as reasonably practicable, especially in cases where there is no data on the permissible exposure limit

� Use of personal protective equipment (PPE) as a last resort

1. Prioritise the control measures at the source, not the worker

� Controlled source means –

Principle of Risk Control

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� Controlled source means –

�Controlled exposure

� A hazard free environment

� It is easier to control processes, machinery and

equipment than to control workers

2.Prioritise the elimination of hazards, not

the reduction of exposure

� No hazard means no exposure

Principle of Risk Control

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� No hazard means no exposure

� Elimination of hazards is more effective

� Reduction of exposure is only recommended

where it is not possible to eliminate or isolate the

hazard

3.Controls should target below the permissible exposure limits

Principle of Risk Control

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permissible exposure limits

� Risk is reduced if worker exposure is below the

permissible limits

� Exposure beyond the permissible limits is harmful

to worker health

� Violation of Regulations, if PEL is exceeded

4.Controls should be as low as reasonably practicable (ALARP), especially in cases where

there is no data on the permissible exposure limit

Principle of Risk Control

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there is no data on the permissible exposure limit

� The risk of cancer or allergy exists even at low exposure levels

� Hazard free environment is still the best working environment

� Many chemicals do not have permissible exposure limits

5.Use of personal protective equipment (PPE) as a last resort

� Successful use of PPE depends on worker cooperation and

Principle of Risk Control

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� Successful use of PPE depends on worker cooperation and training on proper use and maintenance of PPE.

� To be effective, PPE needs to be worn at all times

� Use of PPE is:

� A temporary measure

� An addition to other control measures

� When other methods are not practicable

� It is a list of protection strategies that are rated in order of priority from the best to the worst.

Hierarchy of Risk Controls

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worst. 1. Elimination

2. Substitution

3. Isolation

4. Engineering controls

5. Administrative controls - Safe work practices and procedures

6. Personal Protective Equipment (PPE)

� 1.Hazard Elimination

� Prohibition of use

– Prohibition of the use of :

Hierarchy of Risk Controls

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Prohibition of the use of :

� benzene as a grease remover

� White phosphorus in the manufacturing of matches

� Crocidolite (Blue asbestos) in all purposes except for

research or analytical purposes.

Ref: Occupational Safety and Health (Prohibition of Use of Substances) Order 1999.

2. Substitution

� Substituting the hazard with a less

hazardous material/process

Hierarchy of Risk Controls

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hazardous material/process

� Substitute benzene with xylene as a grease

cleaner.

� Sand is substituted with glass beads in the

blasting and abrasive process

Hierarchy of Risk Controls

3. Isolation

� Distance

Distance the hazard from the workers

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– Distance the hazard from the workers

� Cover/Guard

– Cover the hazard

– Place guarding to prevent unwanted entry/access to hazard

4. Engineering Measures

� Chemical

Methods of Risk Control

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– Ventilation, wet process

� Noise

– Noise absorption, soundproofing, damping,

isolating vibration

� Heat stress

– Automation, local temperature control

5. Administrative Controls (Work Practices and Procedures)

� Chemical

– Safe operating Procedures (SOP); limiting duration of

Methods of Risk Control

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Safe operating Procedures (SOP); limiting duration of exposure

� Noise

– Job rotation; scheduling of heavy machinery operations

� Heat stress

– Hourly rests in cooler temperatures; increasing water intake; acclimatisation

� Provide Information, instruction and training

to workers.

Other Methods to increase the levels of Control on health risk at the Workplace

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� Exposure monitoring

� Health surveillance

� First aid and emergency facilities

� Warning signages

6. Personal Protective Equipment

� Head protection

� Hands protection

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� Respiratory protection

� Hearing protection

� Body protection (protective clothing)

� Foot protection.

Unit 2 – Review Questions

1. What are the 2 key roles of Industrial Hygiene Practitioners?

2. Define the term Industrial Hygiene as given by the IOHA?

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3. What are the four basic principles of industrial hygiene?

4. List the various categories of Health Hazards?

5. In the risk evaluation process, what are the three factors that you would consider to decide on your risk conclusion?

6. List the Hierarchy of Risk Controls?

Thank You.

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Thank You.