Occupational Health, Hygiene and Worker Welfare
Health hazards and exposure routes
Occupational health addresses health hazards: chemical (inhalation, ingestion, skin absorption), physical (noise, vibration, heat, radiation), biological, ergonomic and psychosocial. Candidates must know the routes of entry and that skin absorption and inhalation dominate in industry. Recognise that health effects are often latent - the exposure today may cause disease years later, which is why monitoring and health surveillance exist.
The hygiene paradigm
Anticipate, recognise, evaluate, control. Evaluation uses workplace exposure limits (typically 8-hour time-weighted averages and short-term limits) compared against measured exposure. Traps: confusing a WEL with a legal maximum that can never be exceeded; ignoring peak/short-term exposures; and forgetting that mixed exposures and extended shifts change the effective limit.
Health surveillance
Surveillance is required where a valid technique exists and the hazard is known to cause identifiable disease - audiometry for noise, spirometry for respiratory sensitisers, skin checks for dermatitis, biological monitoring for lead or solvents. It is not a substitute for control, and results are confidential medical records, not general HR files.
Worker welfare
Accommodation standards, potable water, sanitation, rest breaks, heat stress management (midday break rules, hydration, acclimatisation), and access to medical care are welfare obligations. Heat illness prevention is heavily examined: acclimatisation schedules, shaded rest, cool water, and recognising heat exhaustion versus heat stroke.
Rule of thumb
If a question asks how to confirm a control is working for a health hazard, the answer is exposure monitoring plus health surveillance, not PPE compliance checks alone.