55  Industrial Health and Hygiene: Concept and Scope, Occupational Health Hazards (Physical · Chemical · Biological · Ergonomic · Psychosocial), Industrial Hygiene Cycle (Anticipation · Recognition · Evaluation · Control), Statutory Health Provisions (Sections 11-20 Factories Act, ESI Act 1948) and the OSH&WC Code 2020

55.1 Health is Productive Capital

A healthy worker is a productive worker. Industrial health is the positive state of physical, mental and social well-being of workers in relation to their occupation, while industrial hygiene is the anticipation, recognition, evaluation and control of workplace conditions that may harm worker health. Together they form the public-health side of occupational safety law. Indian statutory protection lies in Chapter III of the Factories Act 1948 (Sections 11-20), the Mines Act 1952, the ESI Act 1948 and is now consolidated in the Occupational Safety, Health and Working Conditions Code 2020.

55.2 1 · Concept and Definitions

TipIndustrial Health vs Hygiene
Term Substance
WHO Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity
ILO/WHO Joint Committee (1950) Occupational health aims at the highest degree of physical, mental and social well-being of workers in all occupations
Industrial hygiene The science of anticipation, recognition, evaluation and control of workplace environmental factors that may cause illness or impair well-being

55.3 2 · Objectives of Occupational Health

The 1950 ILO/WHO Joint Committee, revised in 1995, set out five objectives:

  1. Promotion and maintenance of workers’ health and working capacity.
  2. Improvement of working environment and work to make them conducive to safety and health.
  3. Development of work organisation and culture supporting health.
  4. Prevention of occupational diseases and injury.
  5. Adaptation of work to the worker — not the worker to the work.

55.4 3 · Occupational Health Hazards

TipFive Categories of Hazards
Hazard category Examples
Physical Noise, vibration, heat, cold, illumination, radiation, humidity
Chemical Gases, dust, fumes, vapours, mists, solvents, acids, alkalis, metals (lead, mercury)
Biological Bacteria, viruses, fungi, parasites — agriculture, healthcare, sewage workers
Ergonomic Repetitive motion, awkward postures, manual handling, force, vibration
Psychosocial Stress, monotony, shift work, harassment, long hours

55.5 4 · Industrial Hygiene Cycle — ARE-C

TipIndustrial Hygiene Process
Stage Substance
Anticipation Identify potential hazards before workers are exposed (design stage)
Recognition Identify hazards in the existing work environment
Evaluation Measure exposure — environmental monitoring, dose-response, comparison with limits
Control Apply controls — elimination, substitution, engineering, administrative, PPE

55.6 5 · Hierarchy of Controls

TipHierarchy of Controls — most to least effective
Tier Control Example
1 Elimination Remove the hazard entirely
2 Substitution Use less hazardous material
3 Engineering controls Enclosure, ventilation, shielding
4 Administrative controls Work rotation, training, signage
5 PPE Helmets, gloves, masks, respirators (last resort)

55.7 6 · Statutory Health Provisions

55.7.1 Factories Act 1948 — Sections 11-20

TipHealth Provisions — Factories Act
Section Provision
11 Cleanliness — daily sweeping, painting, varnishing
12 Disposal of waste and effluent
13 Ventilation and temperature — wet-bulb temperature, fans
14 Dust and fume removal
15 Artificial humidification
16 Overcrowding — minimum 14.2 m³ air space per worker
17 Lighting — sufficient and suitable
18 Drinking water — wholesome, near workplace; marked “Drinking water”; if 250+ workers, cool drinking water
19 Latrines and urinals — separate for male/female
20 Spittoons
NotePYQ trap — 14.2 m³ minimum air space per worker

Section 16 mandates a minimum of 14.2 m³ of air space per worker (not less than 9.9 m³ for factories pre-1949). NTA stems test this figure.

55.7.2 Mines Act 1952

Provides for sanitation, ventilation in underground mines, drinking water, latrines, conservancy and medical examinations. Pithead baths and crèches are mandatory.

55.7.3 ESI Act 1948

Provides medical benefit, sickness benefit, maternity benefit, disablement benefit, and dependants’ benefit for insured workers in covered establishments.

55.8 7 · Permissible Exposure Limits

Workplace exposures to noise, dust, chemicals are subject to Permissible Exposure Limits (PEL) or Threshold Limit Values (TLV) per:

  • ACGIH (American Conference of Governmental Industrial Hygienists) TLVs — global reference.
  • Indian Standards by Directorate General of Factory Advice Service and Labour Institutes (DGFASLI).
  • Schedules under various rules under Factories/Mines/Building Acts.

For example: noise — 90 dB(A) for 8 hours; dust — varies by type (free silica is most restrictive).

55.9 8 · Indian Institutional Framework

TipKey Indian Institutions
Body Role
DGFASLI Statutory technical authority under Ministry of Labour — advises on safety, health, hygiene
Central Labour Institute (Mumbai) Training and research
National Institute of Occupational Health (NIOH), Ahmedabad Under ICMR — research, surveillance, diagnosis
Regional Labour Institutes (Kanpur, Kolkata, Chennai) Regional training
Directorate General of Mines Safety (DGMS), Dhanbad Safety/health regulation in mines

55.10 9 · Occupational Health Service

A typical occupational health service at the plant includes:

  • Pre-employment medical examination.
  • Periodic medical examination.
  • Treatment of occupational and non-occupational illnesses.
  • First-aid and emergency care.
  • Health education and counselling.
  • Workplace inspection and hazard surveillance.
  • Maintenance of medical records.

55.11 10 · Indian Practice — Numbers

TipSelected Numbers
Provision Threshold / Number
Minimum air space per worker 14.2 m³ (post-1949 factories)
Cool drinking water Where 250+ workers (Section 18)
First-aid box One per 150 workers (Section 45)
Ambulance room Where 500+ workers
Canteen Where 250+ workers (Section 46)
Rest room Where 150+ workers
Crèche Where 30 women workers
Welfare Officer Where 500+ workers

55.12 11 · Position under the OSH&WC Code 2020

The Occupational Safety, Health and Working Conditions Code 2020 consolidates the Factories Act 1948, Mines Act 1952, Plantations Labour Act 1951, Contract Labour Act 1970, ISMW Act 1979, BOCW Act 1996 and other Acts. Key features:

  • Uniform threshold definitions (factory = 20 with power / 40 without power).
  • National OSH Advisory Board — central.
  • Free annual medical examination for workers above 45 years.
  • Mandatory letter of appointment.

55.13 12 · Critique

  • Enforcement gap — limited factory inspectors; informal sector excluded.
  • No comprehensive notifiable occupational disease registry in many states.
  • PPE-last-resort principle often violated.
  • Mental health and stress under-recognised.

55.14 Practice Questions

Q 01DefinitionMedium

WHO defines health as:

  • AAbsence of disease
  • BComplete physical, mental and social well-being
  • CPhysical fitness
  • DLife expectancy
View solution
Correct Option: B
WHO 1946 definition.
Q 02Air spaceMedium

Section 16 of the Factories Act requires minimum air space per worker of:

  • A9.9 m³
  • B14.2 m³
  • C20 m³
  • D25 m³
View solution
Correct Option: B
14.2 m³ for post-1949 factories.
Q 03HierarchyHard

In the hierarchy of controls, the most effective measure is:

  • APPE
  • BAdministrative controls
  • CElimination of the hazard
  • DTraining
View solution
Correct Option: C
Elimination is highest tier.
Q 04HazardsMedium

Repetitive motion and awkward posture are which type of hazard?

  • APhysical
  • BChemical
  • CErgonomic
  • DBiological
View solution
Correct Option: C
Ergonomic hazards.
Q 05CycleMedium

The industrial hygiene cycle has stages:

  • APlan-Do-Check-Act
  • BAnticipation, Recognition, Evaluation, Control
  • CDiagnose-Treat-Follow-up
  • DSurvey-Test-Treat-Recover
View solution
Correct Option: B
ARE-C model.
Q 06DGFASLIHard

DGFASLI stands for:

  • ADirectorate General of Factory Advice Service and Labour Institutes
  • BDirector General of Field Audit Services and Labour Inspectors
  • CDirectorate of General Factory Administration and Service Inspection
  • DDirectorate of General Factories and Labour Income
View solution
Correct Option: A
Factory Advice Service and Labour Institutes.
Q 07NIOHHard

NIOH (National Institute of Occupational Health) is at:

  • AMumbai
  • BAhmedabad
  • CDhanbad
  • DKanpur
View solution
Correct Option: B
NIOH Ahmedabad (under ICMR).
Q 08DGMSMedium

DGMS, the safety regulator for mines, is headquartered at:

  • AMumbai
  • BDhanbad
  • CKanpur
  • DDelhi
View solution
Correct Option: B
DGMS Dhanbad.
Q 09VentilationEasy

Ventilation and temperature provisions are in:

  • ASection 11 Factories Act
  • BSection 13 Factories Act
  • CSection 17 Factories Act
  • DSection 46 Factories Act
View solution
Correct Option: B
Section 13.
Q 10Cool waterMedium

Cool drinking water (Section 18) is required where workforce exceeds:

  • A50
  • B150
  • C250
  • D500
View solution
Correct Option: C
250 workers.
Q 11StressMedium

Workplace stress and shift work fall under:

  • AChemical hazards
  • BPhysical hazards
  • CPsychosocial hazards
  • DBiological hazards
View solution
Correct Option: C
Psychosocial category.
Q 12Joint CommitteeHard

The ILO/WHO Joint Committee on Occupational Health was first set up in:

  • A1948
  • B1950
  • C1981
  • D1995
View solution
Correct Option: B
1950, revised 1995.
Q 13PPEMedium

PPE in the hierarchy of controls is regarded as:

  • AFirst line of defence
  • BLast line of defence
  • CEqual to elimination
  • DAlways preferred
View solution
Correct Option: B
PPE = last resort.
Q 14Health codeEasy

Occupational health and safety is now consolidated under:

  • ACode on Wages 2019
  • BCode on Social Security 2020
  • COSH&WC Code 2020
  • DIR Code 2020
View solution
Correct Option: C
OSH&WC Code 2020.
Q 15MatchHard

Match hazard with example:

(i) Physical (a) Solvent vapours
(ii) Chemical (b) Tuberculosis bacteria
(iii) Biological (c) Heat stress
(iv) Ergonomic (d) Awkward posture
  • A(i)-(c), (ii)-(a), (iii)-(b), (iv)-(d)
  • B(i)-(a), (ii)-(b), (iii)-(c), (iv)-(d)
  • C(i)-(d), (ii)-(c), (iii)-(b), (iv)-(a)
  • D(i)-(b), (ii)-(d), (iii)-(a), (iv)-(c)
View solution
Correct Option: A
Physical-Heat; Chemical-Solvent; Biological-TB; Ergonomic-Posture.
Q 16First-aidHard

First-aid box in factories is required at the ratio of:

  • AOne per 50 workers
  • BOne per 150 workers
  • COne per 250 workers
  • DOne per 500 workers
View solution
Correct Option: B
Section 45 — one per 150.
Q 17AmbulanceHard

An ambulance room is required at workforce of:

  • A150 or more
  • B250 or more
  • C500 or more
  • D1000 or more
View solution
Correct Option: C
500+ workers.
Q 18TLVHard

Threshold Limit Values (TLV) are published by:

  • AACGIH
  • BWTO
  • CWIPO
  • DIAEA
View solution
Correct Option: A
American Conference of Governmental Industrial Hygienists.
Q 19Workplace adaptationMedium

A foundational principle of occupational health is to:

  • AAdapt the worker to the work
  • BAdapt the work to the worker
  • CSpeed up production
  • DCut costs
View solution
Correct Option: B
Work to worker — ILO/WHO principle.
Q 20Code 2020Medium

Under the OSH&WC Code 2020, annual free medical examination is mandatory for workers above:

  • A30 years
  • B40 years
  • C45 years
  • D55 years
View solution
Correct Option: C
Above 45 years.

55.15 Quick Recall

ImportantQuick recall
  • Industrial health = positive well-being of workers; industrial hygiene = anticipation, recognition, evaluation, control (ARE-C).
  • Five hazard categories: Physical, Chemical, Biological, Ergonomic, Psychosocial.
  • Hierarchy of controls (most → least): Elimination → Substitution → Engineering → Administrative → PPE.
  • Factories Act 1948 — health provisions in Chapter III / Sections 11-20. Key thresholds: 14.2 m³ air space; cool water at 250+; first-aid 1/150; ambulance at 500+.
  • Indian institutions: DGFASLI (Mumbai), NIOH (Ahmedabad, under ICMR), DGMS (Dhanbad), Central Labour Institute and Regional Labour Institutes.
  • ILO/WHO 1950 (revised 1995) — five-point occupational health framework.
  • Threshold Limit Values (TLV) by ACGIH; Indian standards by DGFASLI.
  • OSH&WC Code 2020 — consolidates Factories, Mines, Plantations, BOCW, Contract Labour, ISMW Acts; annual free medical examination for workers above 45.
  • Adapt the work to the worker” — foundational ILO/WHO principle.