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Occupational Health Overview

Diploma in Safety & Health Course Programme

Tay Kay Chuang

MSc.in OSH (USA)

Topic No. 1

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Scope

1. Brief History of Occupational Health2. Definition of Occupational Health 3. Focus of Occupational Health 4. Various disciplines of Occupational Health5. Safety versus Health6. Health Hazards7. Concept of Prevention and Control

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1. Occupational Health History

A. Ancient times, Middle Ages, and the Renaissance1. Ancient Times Miners of Ancient times (slaves, prisoners or criminals). Poor working conditions (almost a complete disregard for workers’ safety and health) in

gold, silver and lead mines of Ancient Greece and Egypt.2. Middle Ages Mining in Central Europe had become a skilled occupation. Intensified mining - mines got deeper and conditions worsened (Premature deaths of

workers mainly due to pulmonary diseases – silicosis + TB).3. RENAISSANCE Mining, metal work & other trades flourished in Italy. First systemic study of trade diseases by Bernardino Ramazzini, 1633-1714(Father of

Occupational Medicine) was based on visits to workshops.

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1.Occupational Health History continued ..

B. Industrial Revolution in Great Britain Latter half of 18th Century, Mechanization transferred the making of textiles from

peoples’ homes to the new factories. Problems : Workers of all grades exposed to pressures of increasing productions

(physical & psychological hazards at work)

Effects of industrialisation on Community health Family life disrupted as men moved into new industrial areas leaving

families behind Situation encouraged alcoholism and prostitution Epidemics due to overcrowding in unsanitary conditions. Malnutrition (poverty and unemployment)

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1. Occupational Health History continued ..

Effects of industrialisation on worker health

• Workers in factories were exposed to hazards of occupational disease (wide range of chemicals)

• Workers had to work excessively long hours.

• Untrained Workers had to handle new machinery equipped with poor safety devices – high incidence of injuries

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First Factory Act– 1819 (UK)

The first Factory Act was passed in 1819. It was applied to textile mills and laid down hours of work and regulations covering education and hygiene and child labour. The Act was known thereafter as the Magna Carta of Childhood and marked the first protection of the children of the poor from toil, starvation and ignorance.

Examples:

1. Children below 18 :• Not allowed to work in textile mills after 8.30pm till 5.30am• Not allowed to work more than 12 hours in a day or 65 hours per

week2.Meals break – not < 1.5 hours3.Unlawful to employ children who did not complete their nineth year of education to work in any factory.4.Unlawful to let children < 11 years old to work in factory > 9 hrs/day or > 48 hours per week

1. Occupational Health History … …continued

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1. Occupational Health History …continued

Influence from developments in Medicine

Agricola and Paracelcus (15th Century) Physicians who made their first observations on miners and their diseases

Bernardino Ramazzini (1633-1714) Father of Occupational Medicine who made first systemic study of trade

diseases based on visits to workshops and described the associated treatment and preventive measures.

He recommended that physicians should routinely enquire about a patient’s occupation.

Percivall Pot (1713-88) Drew attention to soot as a cause of scrotal cancer in chimney sweeps.

Charles Turner Thackrah (1795-1833) Published the first British work on occupational diseases.

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Class Exercise No.1

1. In the Ancient times, why were prisoners, criminals and slaves being asked to work in mining metals?

2. Why was Dr. Ramazzini recommended that doctors when seeing sick workers should ask for their occupation?

3. What were the social impacts of Industrial Revolution in UK in the later half of 18th Century , when machines were widely used for textiles making?

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2. Definition of Occupational Health

Promotion and maintenance of the highest degree of the physical, mental and social well-being of workers in all occupations;

Prevention from amongst workers of ill-health caused by their working conditions;

Protection of workers in their employment from risks resulting from factors adverse to health;

Placing and maintenance of workers in an occupational environment adapted to their physiological and psychological ability.

Aim – To adapt work to man and each man to his job.

ILO / WHO committee on Occupational Health

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3. Focus of Occupational Health Promote and maintain workers’ optimal Health.

Physical fitness to work Mentally sound (work-life balance; cordial work relationship) Social health (happy family , good nutrition no social ills such as alcohol & drugs

abuse, prostitution) Prevention from illnesses or diseases arising from the workplace or work

processes. Anticipation, identification, evaluation, control and review of hazards/risks.

Improve quality of work environment and work processes to suit workers’ physiological and psychological capabilities . Improve work space and means of access for workers to maintain

equipment (preferably at design stage).

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Focus of Occupational Health

…continued

Concept of Promotion and Prevention

Occupational Health DiseasesWorkplace Accidents

Factors relating to work

-Hazards

-Work environment

- Working methods

-Equipment, machinery etc

Healthy Lifestyle

-No Smoking

-No Alcohol and drug

-Hobbies that promote health

Prevention Promotion

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Class Exercise No. 2

1. Give 3 examples each of adverse factors that may harm the well-being of workers in terms of

Physical health Mental health and Social health

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4. Occupational Health Disciplines

Occupational Medicine Industrial Hygiene Occupational Toxicology Ergonomics Epidemiology Industrial Psychology

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Occupational MedicineMedical specialty concerned with the promotion and maintenance of the physical and mental health of employees in occupational settings.

• assessment of workers’ health • linking working conditions and processes to workers’ health• assisting in managing the health, skills and working capacity of

the entire working population and • managing individual cases in the context of working ability and

production

Industrial hygienePreventive science devoted to anticipation, recognition, evaluation and control of health hazards at the place of work

ToxicologyStudy of chemical or physical agents that produce adverse responses in the biological systems with which they interact.

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Ergonomics

It is a scientific approach of how to fit the task demands of the workplace to the employee who perform the task.

Epidemiology

The study of the distribution and determinants of health-related states in specified populations, and the application of this study to control of health problems. Distribution – refers to analysis by time, place, and classes of person affected. Determinants – all the physical, biological, social, cultural, and behavioural factors that influence health.

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Recent trends in OH

Last 30 years incidence Occupational Diseases (OD) reduced methods to detect early OD monitoring of workers’ exposure to health risks allows early

detection of OD epidemiology establishes exposure & diseases Exposure standards develop

These are largely due to improvement in technology, safer and healthier work environment, positive work behaviour of workers and employers, and introduction of OSH legislation to protect the safety and health of people at work.

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5. Relationship between Occupational Safety and Occupational Health

Safety prevention of accidents (risks from moving machinery,

fire and explosions, lightning, falling objects, sharp objects, acid burn, etc.)

Health Prevention of diseases (risks from chemical, physical,

biological, ergonomics & psychological agents)

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Cause and Effect

CAUSE

EFFECT

SAFETY HEALTH

CAUSE

EFFECT

Heredity

Previous

Exposures

Time

Dose

Lifestyle

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Causes and Effects

Musculo-Skeletal Disorders (MSD)

Dermatitis

StressMetal Fume fevers

NIHL

Mesothelioma

Leukaemia

Lung cancer

Accidents

SolventEffects

Welder’s Flash

Minutes Days Months Years Decades

Cause is

hard to see

Cause is

easy to see

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Hazard and Risk

HAZARD

Potential of an agent to cause harm to health

RISK

Likelihood that an agent will cause harm to health in the actual circumstances of

exposure

RISK = HAZARD X EXPOSURE

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Hazard v RiskHazard- The potential of a chemical to cause harm

to an individual The Hazard relates to the intrinsic

properties of the chemical (its physicochemical properties and health effects) to cause harm and will always be the same

Risk- The likelihood of harm to worker

occurring under the actual circumstances of exposure The Risk is totally dependant on the actual

exposure (Intensity or magnitude x duration x frequency) to the agent.

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7. Health Hazard types

2 basic Categories Acute and ChronicAcute

An acute effect is caused by short period of exposure (e.g. in seconds or minutes) to high concentrations of a substance.

Example: The acute effect of carbon monoxide (CO) poisoning where a brief exposure to a high CO concentration causes asphyxiation.

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Hazards Types

Chronic Effects Chronic or long-term effects are caused by

repeated or prolonged exposure (continuing day after day or week after week), typically involving relatively low levels of a substance.

Example: Silicosis (causing fibrosis of lungs) is due to prolonged exposure over a number of years to crystalline silica.

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Classification of Health Hazards

1. Physical 2. Chemical 3. Biological 4. Ergonomic 5. Psychological

There are 5 general groups of Health Hazards

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1.1. Physical HazardsPhysical Hazards

From NoiseFrom Noise

From LightFrom Light

Examples of the 5 Groups of Health Hazards

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From Temperature Coldness

Heat stress

Vibration

Radiation

1.1. Physical Hazards:Physical Hazards:

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From Welding Fume, Mineral oils, Paints,, Silica sand, Acids, Alkalis, Solvent (Thinner, Adhesive, Benzene, Diesel).

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•Bacteria (e.g. E.Coli, Staphylococci,TB, legionella);•Virus(e.g. Hepatitis A,B & C, HIV, SARS, Avian Influenza);•Fungus & Spores

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Manual lifting, Posture, Repetitive Movement, Space, Comfort.

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ERGONOMIC HAZARDS

Air temperature too hot/cold, low relative humidity

Poor design, inaccessibility,insufficient space, awkward postures

Mismatch of work environment

WorkstationToo bright/dim

Manual lifting

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Mental stress, Overwork, Work Pressure, Long Shift Hours / work Schedule-night duty, offshore duty roster, boredom, Unreasonable deadline ,cultural shock., poor communications, monotonous work

Increase risk of incident.

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Routes of Entry of “Poisons” into human body

Inhalation- most significant route of entry (respiratory system)

Absorption (through skin, eye and mucous membrane)

Ingestion (mouth) Injection

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8. Principles of Prevention and control Systematic approach

to control of hazards thorough

understanding of process required

Control hierarchy Closing the loop

Review

Anticipation

Identification/recognition

Assessment/Evaluation

Control

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8. Principles of Prevention & Control1. Anticipation Predict or expect dangerous situations before they occur and take steps to prevent them.

2. Identification/Recognition Identify hazardous situations (worksite audit, incident investigation report, literature,

exposure monitoring) Understanding work process and materials used

3. Assessment/Evaluation Assess work process and risks involved Can be qualitative or quantitative assessment involving ther services of experts

4. Controls Implemented based on risks identified. Preferred methods

Hierarchy of control principle. Principle of ALARP

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The hierarchy of controls is a list in preferential order of the means by which exposure to health hazards can be controlled Elimination Substitution (alternatives) Engineering (plant and equipment) Procedural Personal protective equipment

Hierarchy of controls

Effectiveness of Controls

The types of control vary in their effectiveness according to the control hierarchy:

Elimination Most Effective

Substitution

Engineering

Procedural

PPE Least Effective

Types of controls

Elimination and substitution Engineering (plant and equipment):

Equipment/processes designed to prevent or minimize release of the hazard

Examples: containment (enclosure), exhaust ventilation, waste treatment process

Types of controls Procedural:

Safe systems of work / Permit to work system

Record systems

Staff Instruction, Information & training

Supervision, Emergency arrangements

Personal Protective Equipment (PPE):

Respiratory & Skin Protection as a secondary line

of defence or as the only option

last line of defence – least effective

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Definitions of ALARP ALARP = As Low As Reasonably Practicable.“ This means “ balancing the reduction in risk against : State of knowledge about the hazard or risk Availability and suitability of ways to remove or mitigate the hazard or risk; cost of removing or mitigating the hazard or risk ALARP level represents the point, objectively assessed

based on existing knowledge, at which the time, difficulty and cost of further reduction measures become unreasonably disproportional to the additional risk reduction obtained.

ALARP Definition

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••

••

•

•

Risk toHealth

Tolerability level

Cost ofControl

ALARPLegal Liability Wasteful

ALARP

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Principles of Prevention & Control

5. REVIEW

Regular review by management for continual improvement on safe work practice.

Examples: Workplace inspection or OSH Management System audit Review on the close-out status of follow-up actions on

inspections, audits or incident investigation reports. Review on effectiveness of control measures.

Class Exercise No. 3Identify 2 Health Hazards and their Harmful Effects at your Workplace or home

Hazard Source Route Harmful Effect

1. Physical

2. Chemical

3. Ergonomic

4. Biological

5. Psychological