occupational health basics for 4th year MBBS

1. 1
DR AMBREEN ANSAR

2. Aim
2
Students should be able to apply the basic principles of
occupational medicine to their professional practice
as doctors.

3. Objectives
3
 At the end of the unit student should be able to:
 Delineate occupational health, occupational hygiene,
ergonomics, occupational diseases & Injuries.
 Enlist occupational disease agents and factors (physical,
chemical, biological, psychological, mental).
 Identify factors or patterns in a patient’s history that may
indicate a work related contribution to ill health.
 Suggest preventive and/or corrective measures.

4. Layout of our study plan
4
 Introduction and physical hazards
 Chemical hazards
 Biological hazards
 Occupational diseases
 Occupational disorders
 Occupational accidents
 Ergonomics

5. Occupational Medicine/Health
5
a branch of medicine concerned with
the interaction between health and
work (“occupation”)
 The joint international labor organization committee
on Occupational health, 1950 defined occupational
health as
“The highest degree of physical,
mental and social well-being of
workers in all occupations.”

6. Occupational/industrial hygiene
6
 “The science and art devoted to the anticipation,
recognition, evaluation and control of environmental
factors/stresses that arise in a workplace and that
may cause sickness, impaired health and well being
or discomfort and inefficiency among workers or
citizens of the community.”

7. ERGONOMICS
7
 Ergonomics is the study of men at work with a view
to identify the stress factors operating in work
environments and impairing the health of the
workers and interfering with their work
performance.

8. 8
Why is occupational health and safety
important?

9. Why is occupational health needed?
9
 Is responsible for the
promotion and maintenance
of the highest degree of physical,
mental and social well-being of
workers in all occupations.
 Prevents that workers have
adverse effects on health caused
by their working conditions.

10. Case scenario
10
Suppose you are an occupational physician.
A 31-year-old laboratory technician is referred to your
clinic by her manager, because of alleged lateness
and poor performance at work. You are asked to
assess whether there is an underlying medical cause
for this.

11. History
11
 She tells you that she has not been sleeping well
lately, possibly due to nocturnal coughing. She says
the lab is cold and damp and that by the end of the
working day her right arm is aching. She says that
when she told her manager, he was unsympathetic;
telling her she should leave if she doesn’t like the job.

12. Scenario 2
12
A brick kiln laborer was brought unconscious to the
emergency. He was hypotensive and sweating
profusely.

13. Scenario 3
13
A person employed in the welding section of an
automobile manufacturing plant reported
sick with redness of eyes and impaired vision.
Examination confirmed the diagnosis of
conjunctivitis.

14. QUESTIONS
14
1. What are the presenting medical problems?
2. What are the possible work-related causes of their
symptoms?
3. How might you classify the potential hazards in
their workplace?
4. How will you respond to the manager’s questions?
5.What preventive measures will you suggest for these
patients?

15. Aims of occupational health
15
1. To IDENTIFY & bring under control all the
agents (physical, chemical, biological, mechanical
& psychological) that are known or suspected to be
hazardous.
2. To ENSURE that the physical & mental demands
imposed on people match with their physiological
& psychological capabilities, needs & limitation.

16. Aims of occupational health
16
3. To PROTECT the vulnerable and enhance their
resistance to adverse working conditions.
4. To DISCOVER and IMPROVE work situation that
contribute to the ill-health of workers.
5. To EDUCATE management and workers to fulfill their
responsibilities relevant to health protection and
promotion.
6. To CARRY OUT comprehensive in-plant health
programmes which deal with man’s total health.

17. Main activity areas of occupational health
17
1. Identification & improvement
2. Matching & protection
3. Education & motivation
4. Holistic approach

18. Types of diseases among workers
18
 Occupational diseases are restricted to
predisposed occupational groups and are not seen in
non-occupational settings. For example occupational
skin disorders, occupational cancers etc.
 There may be non-occupational diseases which
are prevalent in the community outside the
occupational settings. For example cholera, typhoid,
malaria etc.

19. Types of diseases among workers
19
 Partly occupational diseases or work related
diseases are comparatively more frequent among
industrial workers for example IHD, HTN, Peptic
ulcer & psychosomatic illnesses.

20. FUNCTIONS OF OCCUPATIONAL
HEALTH SERVICE
1. Pre-employment medical examination.
2. First Aid and emergency service.
3. Supervision of the work environment for the control
of dangerous substances in the work environment.
4. Special periodic medical examination particularly for
the workers in dangerous operations.
5. Health education for disseminating information on
specific hazards and risks in the work environment.
20

21. FUNCTION OF HEALTH
SERVICE - CONT..
6. Special examination and surveillance of health
of women and children.
7. Advising the employer or management for
improving working conditions, and placement
of hazards.
8. Monitoring of working environment for
assessment and control of hazards.
9. Supervision over sanitation, hygiene and
canteen facilities.
21

22. FUNCTION OF HEALTH
SERVICE - CONT..
10. Liaison and cooperation with the safety committees
11. Maintenance of medical records for medical check-up
and follow-up for maintaining health standards and
also for evaluation.
12. To carry out other parallel activities such as nutrition
programme, family planning, social services recreation
etc. Concerning the health and welfare of the workers.
22

23. Types of occupational environment
 Internal environment:
23
 Industrial settings, offices, schools, hotels, hospitals, labs, & all
government and private establishments.
 External environment:
 Extra industrial like environment for farmers, sailors, sheep
herders, construction workers and other field workers.

24. 24
 Residential environment:
 66% of time is spent at homes; if congenial & comfortable it
will favourably effect industrial environment.

25. Occupational hazards
25
 May be categorized in two ways:
 According to target organ system
 According to type of agent involved

26. a. According to type of agent involved
 Physical hazards
 Chemical hazards
 Biological hazards
 Psychosocial hazards
26

27. 1. Physical hazards
27
1. High or low temperatures
2. Low pressures
3. Vibration
4. Noise
5. Ionizing radiation
6. Non-ionizing radiation

28. High temperature
28

29. 1. High temperatures
 Decrease efficiency
 Increased fatigue
 Increased accident rates
 Heat cramps
 Heat exhaustion
 Heat stroke
29

30. 30
 Comfort zone lie between:
 69-80 ◦F or
 20-27 ◦C
 Occupations at risk:
 Radiant heat in foundry, glass & steel industry
 Heat stagnation in jute & cotton industry.

31. 2. Low temperatures
 Chilblains
 Trench foot
 Frost bite
31
 Occupational exposures among:
 Caisson workers, commercial fisherman, divers, dairy workers,
refrigerator repairmen & outside workers in cold northern
regions.

32. 32

33. 33

34. Prevention & control
2. Case management
3. Health education
34
1. Personal protection
1. Clothing
1. Warm/Light
2. Heat resistant
2. Metal heat refractors
3. Periodic salt & water
intake
4. Ear muffs
5. Goggles
6. Aprons and boots
7. Regulated exposure of
workers

35. 3. Low pressures (at high altitude)
 Manifestations of air
expansion
 Barodontalgia
 Barosinusitis
 Barotitis
 Emphysema
 Abdominal distention
35

36. 3. Low pressures (at high altitude)
 Manifestations of nitrogen effervescence
 Bends
 Chokes
 Prickles
 Paralysis
 Aseptic bone necrosis
36

37. 3. Low pressures (at high altitude)
 Occupations at risk are:
 Aviators, deep sea divers, balloonists, air passengers, tunellers
etc.
37

38. 4. Noise
38
 Sound that is unwanted or disrupts one’s quality of life is
called as noise. When there is lot of noise in the
environment, it is termed as noise pollution
 Auditory effects
 Non- auditory effects
 Factors affecting noise injury are intensity,
frequency, range, duration of exposure & individual
susceptibility.

39. Non auditory effects of noise
39

40. 40

41. Control measures
41
 Industrial measures
 Substitution:
 For example riveting by welding, chipping by grinding, spur gears by
spiral gears, blunt tools by sharp tools.
 Reduction:
 By proper maintenance of machine and equipment, replacement of
worn out parts, lubrication of moving components etc.
 Enclosure:
 Creating a sound proof barrier between machine and work area.
 Soundproofing:
 To reduce the reverberation of noise
 Asbestos fibers, vegetable fibres, glass wool, mineral wool used as
blankets, blocks or panels.
 Health education
 Legislation

42. 5. Vibration
42
 Long term exposure to 10-500hz
may lead to:
 Vibration sickness
 Whitening & numbness of fingers
 Reactive hyperemia
 Neurogenic damage
 Osteoarthritic changes
 Damaged tendons, ligaments & nerves
 Occupational exposure among
users of rotary discs, grinding
wheels, drills, chisels & hammers
etc.

43. 6. Non-ionizing radiation
 That do not cause ionization of tissues upon
penetration. These include:
 Infra red
 Ultra violet
 Microwave radiations
 Laser beams
43

44. 44
 Thermal damage to eyes; injury to cornea, iris or lens
 Acute skin burn with hyper pigmentation.
 UV radiation is carcinogenic in addition to causing
photokeratitis, conjunctivitis, erythema, sunburn,
premature ageing of skin, pre-malignant and
malignant conditions.

45. 45
 Microwave injuries include corneal injuries, lens
opacities, frank cataract, retinal damage and
testicular damage with decreased sperm count.
 Laser injuries include corneal, retinal and cutaneous
burns to field construction workers who se lasers to
obtain alignment of dams, tunnels and pipes etc.

46. Sources of radiations
46

47. 7. Ionizing radiation
47
 Exposure occur among workers of
radiology department
 Agents are Co 60, I 131, S 35,
Krypton 85,K 42, Ce 137, Plutonium
139 & Ph 32
 Maximum permissible range is 5
rem/yr/whole body

48. Health effects of acute exposure
48

49. 49

50. Protection from radiation
50
 Industrial measures:
 Personal hygiene
 Not to eat or smoke in restricted areas, no pipetting of radioactive
solutions, no handling of isotopes with open wound, wash exposed
parts before leaving the active area.
 personal protection,
 Use lab clothing and overalls, rubber gloves, canvas shoe covers,
face sheilds, safety goggles, self contained breathing apparatus.
 safety education,

51. 51
 radiation monitoring,
 Use of Radiation monitoring devices such as film badges, pocket
ionizing chambers, pocket dosimeters.
 source shielding.
 Gamma and x ray emitters in concrete chambers, neutron emitters
in water. Paraffin or hydrogen containing substance, beta
radiators in thin plastics, aluminium and thick rubber gloves.

52. Protection from physical hazards
1. Personal protection
52
1. Personal protective equipment
2. Regulated exposure to working environment
2. Case management
3. Health education

53. 2. Chemical hazards
53
 These hazards act in three ways:
 Inhalation
 Gases
 Asphyxiant gases: CO, HCN, H2S
 Irritant gases: chlorine, ammonia, SO2
 Toxic gases: arsine & stibine
 Inert gases: CO2, methane, nitrogen
 Dusts
 Organic: cotton fibre, sugar cane fibre, hay dust, tobacco
 Inorganic: silica, asbestos, coal, iron
 Ingestion & Local action
 Metals
 Type A intoxicants: with local action cadmium, beryllium, nickel
 Type B intoxicants: lead, mercury, manganese

54. 1. Gases which pose occupational threat
 1. Asphyxiant gases:
 Carbon monoxide:
 Exposure to workers in electric, oil or blast furnaces, gas
manufacturing plants, ovens, mines etc
 It cause anaemic anoxia by forming carboxyhemoglobin.
 Symptoms include: headache, dizziness, CNS manifestations.
 Prevention:
 public education on the safe operation of appliances, heaters,
fireplaces, and internal-combustion engines,
 emphasis on the installation of carbon monoxide detectors.
 Equipment maintainence.
54

55. Symptoms of CO poisoning
55

56.  Hydrogen sulphide:
56
 Exposure to sewers, miners breweries, tannaries.
 It paralyses the respiratory center.
 Symptoms include photophobia, lacrimation, salivation, chemosis,
blurring.
 HCN:
 It interferes with respiratory enzymes which are necessary for
tissue oxidation; leads to histolytic anaemia.
 Exposure occurs among foundry workers, dye markers, petroleum
refineries, smelters.
 Symptoms include constriction of chest, hyper apnea, palpitations,
convulsions and unconsciousness.

57. 57
 2. Irritant gases:
Ammonia
• skin
Sulpher
dioxide
• GIT
Chlorine gas
• Nausea
vomiting
 All three gases effect the mucous membrane of ENT &
respiratory tract causing burning sensation, lacrimation,
chemosis, conjunctivitis, rhinitis, coughing, sneezing,
salivation & finally leading to pulmonary edema.

58. 58
 Exposure to chlorine: in dye, textile, paper & chemical
industries where chlorine is used as bleaching or disinfecting
agent.
 Exposure to ammonia: in workers engaged in refrigeration,
cold storage & artificial ice-manufacturing plants.

59. 59
 3. Toxic gases:
 Arsine
 Invade RBCs and lead to hemolysis, hemolytic anaemia, haemoglobinuria
 Garlic like odour.
 Arsine emits toxic fumes of arsenic when heated to decomposition
 Stibine:
 It invades CNS and cause cerebral edema & depression of respiratory
symptoms.
 Exposure occur among workers of semiconductor and metal refining
industries.
 In the event of a fire involving arsine or Stibine, use fine water spray and
liquid and gas tight chemical protective clothing with breathing
apparatus

60. 60
 4. Inert gases:
 Nitrogen, Methane & Carbon dioxide.
 These gases lead to anoxic anoxia by diluting the concentration of
oxygen in air.
 When O2 falls below 12% deep breathing starts
 At 10% markedly deep breathing occurs
 At 8% cyanosis of lips and face is seen
 At 5% consciousness is clouded leading to coma
 Exposure to CO2 occur in mines, tunnels, vaults, cellars, tanks &
from decomposition of sewage.
 Exposure to nitrogen occur in wells, caves & mines.
 Exposure to methane occur in coal mines

61. 2. Dusts causing occupational diseases
61
 Detrimental effects of dusts depend upon the following
factors:
 Fineness i.e size of the particle:
 Particles >10 μm -----settle down due to gravity
 Particles < 10 μm-----remain suspended in air
 Particles 5-10 μm-----arrested in upper respiratory tract
 Particles 3-5 μm-------deposited in mid respiratory tract
 Particles 1-3 μm-------enter and settle in alveoli
 Particles <1 μm--------are constantly in Brownian movement and
settle only when caught by alveoli and adhered to them
 Concentration in air
 Duration of exposure
 Susceptibility of individual

62. Fate of dust particle
62
 The fate of dust particle is decided by their nature
 Organic or inorganic
 Soluble or insoluble
 Inert or fibrogenic
 Soluble dust particles are dissolved and absorbed
into systemic circulation and eliminated by
metabolic process.

63. 63
 Insoluble dust particles are handled by our
physiological responses like coughing, sneezing,
mucociliary activities and defense mechanisms of
phagocytes.
 When these mechanisms are overwhelmed the dust
particles start accumulating in lungs. If these
insoluble particles are fibrogenic they will initiate a
reaction leading to “pneumoconiosis”

64. Pneumoconiosis
64
 Is categorized in two ways:
1.
Inorganic dusts Organic dusts
DUST DISEASE DUST DISEASE
1. Coal Anthracosis 1. Cane fiber Bagassosis
2. Silica Silicosis 2. Cotton dust Byssinosis
3. Asbestos Asbestosis 3. Tobacco Tobacosis
4. Iron Siderosis 4. Hay/ Grain
dust
Farmer’s lung

65. Pneumoconiosis
65
2.
Classification Types of pneumoconiosis
1. Major pneumoconiosis Silicosis, Anthracosis, asbestosis
2. Minor pneumoconiosis Bagassosis, Byssinosis
3 . Benign pneumoconiosis Siderosis

66. Comparative features of different types
66
Features Silicosis Asbestosis Anthracosis
1. Agent/ dust •Silica free or
silicon dioxid or
silicic acid
•Particles are 0.5 -
3 μ are most
dangerous.
•Asbestos fibres
1. Serpentine or
chrysolite
(safer)
2. Amphibole
i. Crocidolite
(blue)
ii. Amosite
(brown, safer)
iii. Anthrophylite
(white)
• 20-500μ in
length and 0.5-
50 μ in
diameter
• Coal dust

67. 67
 Silicosis
 Silica free or silicon dioxid or silicic acid
 Particles of size 0.5 -3 μ are most dangerous.
 Occupational exposure
 Mining, pottery, ceramic, sand blasting, metal
grinding, building & construction work, rock mining,
iron & steel industry.

68.  Pathogenesis
68
 Fibrosis is initiated by silicic acid leading to nodular fibrosis,
emphysema, and right heart failure. Pulmonary tuberculosis
may intervene in 50% of cases.
 Dense nodular fibrosis 3-4 mm nodules and in upper part
of lung.
 Symptoms:
 Irritant cough, dyspnea on exertion & pain in chest.
 X-ray shows “snow-storm” appearence

69.  Asbestosis
 Causative agent:
69
 Asbestos fibres
1. Serpentine or chrysolite (safer)
2. Amphibole
 Crocidolite (blue)
 Amosite (brown, safer)
 Anthrophylite (white)
 20-500μ in length and 0.5-50 μ in diameter

70.  Occupational exposure:
 Manufacturers of Asbestos cement, fire proof textiles, roof
tiling, brake lining & gaskets
 Pathogenesis:
 Asbestos fibers initiate fibrosis of pulmonary tissue,
emphysema and its associated complications.
 Fibrosis is due to mechanical irritation, it is peri-bronchial,
diffuse and basal in location.
 Mesothelioma is commonly associated with asbestosis.
 Symptoms:
 Dyspnea out of proportion, clubbing, cyanosis, cardiac
distress.
70

71. 71
 Sputum shows “asbestos
bodies”.
 X-ray shows ground glass
appearance.

72. Comparative features of different types
72
Features Silicosis Asbestosis Anthracosis
Occupational
exposure
Mining, pottery,
ceramic, sand
blasting, metal
grinding, building
& construction
work, rock mining,
iron & steel
industry.
Manufacturers of
Asbestos cement,
fire proof textiles,
roof tiling, brake
lining & gaskets.
Coal miners, coal
processors & coal
handlers and those
manufacturing
carbon electrodes.
Incubation period 6 months to 6
years
12 years

73. Comparative features of different types
Features Silicosis Asbestosis Anthracosis
73
Pathogenesis Fibrosis is initiated
by silicic acid leading
to nodular fibrosis,
emphysema, and
right heart failure.
Pulmonary
tuberculosis may
intervene in 50% of
cases.
Fibrosis is nodular
and in upper part of
lung.
Asbestos fibers
initiate fibrosis of
pulmonary tissue,
emphysema and its
associated
complications.
Fibrosis is due to
mechanical irritation,
it is peri-bronchial,
diffuse and basal in
location
•Coal dust initiates
diffuse and massive
fibrosis
a. Simple
pneumoconiosis
with ventilatory
impairment.
b. Progressive
massive fibrosis
leading to
emphysema and
right heart failure.
Clinico-Pathologic
features
Irritant cough,
dyspnea on exertion
& pain in chest.
Dense nodular
fibrosis
3-4 mm nodules.
X-ray shows “snow-storm”
appearence
Dyspnea out of
proportion,
clubbing, cyanosis,
cardiac distress.
Sputum shows
“asbestos bodies”.
X-ray shows ground
glass appearance.
•From little
ventilatory
impairment to severe
respiratory disability
leading to pre-mature
death.

74. Silicosis, Anthracosis & asbestosis
X-ray findings
74

75. Byssinosis
 Inhalation of cotton fiber dust
 Symptoms:
 Chronic cough, progressive
dyspnea ending in chronic
bronchitis and emphysema.
 Occupational exposure:
 Textile industry
75

76. Bagassosis
76
 Inhalation of bagasse sugar cane dust
containing thermophilic
actinomycete, thermoactinomyces
sacchari
 Symptoms:
 Breathlessness, cough, haemoptysis, and
slight fever.
 Occupational exposure:
 Manufacturing of paper, cardboard and
rayon.

77. Farmer’s lung
77
 Inhalation of mouldy hay or
grain dust containing
thermophilic actinomycetes,
Micropolyspora faeni
 General & respiratory
symptoms with physical
signs.

78. Comparative features of different types
78
Features Byssinosis Bagassosis Farmer’s lung
Causative agent Inhalation of
cotton fiber dust
Inhalation of
bagasse sugar cane
dust containing
thermophilic
actinomycete,
thermoactinomyce
s sacchari
Inhalation of
mouldy hay or
grain dust
containing
thermophilic
actinomycetes,
Micropolyspora
faeni
Symptoms Chronic cough,
progressive
dyspnea ending in
chronic bronchitis
and emphysema.
Breathlessness,
cough,
haemoptysis, and
slight fever.
General &
respiratory
symptoms with
physical signs.
Occupational
exposure
Textile industry Manufacturing of
paper, cardboard
and rayon.

79. Control of pneumoconiosis
 Rigorous dust control measures
 Substitution, enclosure, isolation, hydroblasting, good house
keeping, personal protective measures
 Regular physical examination of workers.
 Periodic examination of workers, biological
monitoring (X-ray & Lung function)
 Personal protection
 Masks, respirators with mechanical filters
 Regulated exposure
 Health education
79

80.  Bagassosis:
 Bagasse control
80
 Keep moisture content above 20%, spray bagasse with 2%
propionic acid.
 Asbestosis:
 Use of safer types of asbestos (chrysolite & amosite)
 Substitution with other insulants: glass fiber, mineral wool,
calcium silicate. Plastic foams etc.

81. 3. Aerosols
81
 Aerosols of various type are released in metal-processing
industries during smelting, mining &
refining operations.
 Inhalation of aerosols by workers result in metal
intoxication manifested by metal-fume fever,
pulmonary disease and systemic disease.
 Accidental ingestion or their absorption through
exposed skin leads to disturbances of alimentary
tract & various dermatitis.

82.  Group A intoxicants:
82
 Aerosols interacting at local level, lesions restricted to skin and
respiratory tract.
 They include chromium, beryllium & nickel aerosols.
 Group B intoxicants:
 Aerosols interacting at distal levels invaribly affecting CNS
besides other target organs.
 They include lead, mercury and manganese.

83. Lead poisoning
 Occupational exposure:
83
 Production of batteries, welding & flame cutting of lead,
moulding of lead containing alloys in foundries, lead soldering,
spray painting with lead paints and grinding or sand blasting
of lead alloys.
 Sign & symptoms:
 Lead encephalopathy:
 delerium, coma, convulsions, mental dullness, transient paresis &
toxic psychosis.
 Chronic exposure result in poor memory, poor concentration,
headache, transitory deafness and trembling.

84. 84
 Lead palsy:
 Wrist drop, ankle drop
 Lead ophthalmopathy
 Diminution of visual fields, papilloedema,
secondary atrophy and post neurotic atrophy of disc
which may lead to permanent blindness.
 Lead anemia:
 Hypochromic ass with reticulocytosis and stipled
cells.
 Lead colic:
 Peri-umblical or su-umblical area, preceeded by
constipation characterized by severe pain and
perspiration.
 Lead line:
 It is a dark blue stippled line on gums about 1mm
from gingival margin.

85. Diagnosis of lead poisoning
 History
 Clinical features
 Lab diagnosis
85
 Coproporphyrin in urie (CPU)
 Useful screening test. Levels in non-exposed persons are less than
150μg/l
 Aminolevulinic acid in urine (ALAU)
 If it exceeds 5mg/l, it indicates clearly lead absorption.
 Lead in blood & urine:
 Quantitative indicators of exposure
 In urine >0.8mg/l indicates lead exposure (0.2-0.8 is normal)
 In blood >70 μg/100ml is associated with clinical symptoms.

86. 86
 At levels above 80 μg/dL, serious, permanent health
damage may occur (extremely dangerous).
 Between 40 and 80 μg/dL, serious health damage
may be occuring, even if there are no symptoms
(seriously elevated).
 Between 25 and 40 μg/dL, regular exposure is
occuring. There is some evidence of potential
physiologic problems (elevated).
 Between 10 and 25 μg/dL, lead is building up in the
body and some exposure is occuring.
• https://www.health.ny.gov/publications/2584/

87. Preventive measures
 Substitution:
 Isolation
 Local exhaust ventilation
 Personal protection
 Good house keeping
 Working atmosphere:
 Lead concentration should be kept below 2mg/10m3.
 Periodic examination of workers
 Personal hygiene
 Health education
87

88. 88
 Match the diseases related to the occupations shown
in following pictures.

89. 89

90. 90
SILICOSIS

91. 91

92. 92
FARMER’S LUNG
AND WHAT ELSE

93. 93

94. 94
MUSCULAR CRAMPS
DUE TO DEHYDRATION & HEAT

95. 95

96. 96
W O O L S O R T E R ’ S D I S E A S E
ANTHRAX

97. Occupation related psychological and
behavioural disorders
97
 A healthy social climate (any industry or institution)
 Increase the morale of workers
 Increase their output
 An unhealthy social climate
 Psychological stress
 Workers lose interest in their jobs
 They are apprehensive, irritable and unsocial.

98. Behavioural changes
98
 Minor changes like petty jealousies, fault finding &
craving for undue attention
 Leading to major psychological and behavioural
disorders like absenteeism & occupational cramps

99. 1. Absenteeism
99

100. Absenteeism
100
 It is the practice of remaining absent from workfor
one reason or the other.
Sickness Absenteeism
 Means staying absent from work on account of
sickness or injury.
 Only 10% of sickness is of occupational origin
therefore, valid for compensation.

101. History of the lab worker!!!
101
 She tells you that she has not been sleeping well
lately, possibly due to nocturnal coughing. She says
the lab is cold and damp and that by the end of the
working day her right arm is aching. She says that
when she told her manager, he was unsympathetic;
telling her she should leave if she doesn’t like the job.

102. QUESTIONS
102
1. What are the presenting medical problems?
2. What are the possible work-related causes of their
symptoms?
3. How might you classify the potential hazards in
their workplace?
4. How will you respond to the manager’s questions?
5.What preventive measures will you suggest for these
patients?

103. 103

104. Side effects of absenteeism
104
 Beyond acceptable levels it promotes:
 among regular workers
 Annoyance and frustration
 Reduces their morale
 Increases their workload
 Interferes with production of goods in industries
 Increases the cost of finished items

105.  It is a multifactorial disorder
 Personal reasons
 Occupational reasons
 Organizational reasons
 Social reasons
105

106. a. Predisposing personal factors
 Young age
 Immaturity
 Emotional instability
 Short length of service
 Lack of personal motivation
 Destructive life style
 Excessive smoking
 Alcohol consumption
106

107. b. Predisposing occupational factors
107
 Poor physical work environment
 Unpleasant nature of work
 Shift work system
 High degree of motivation
 No incentives for better work performance

108. c.Predisposing organizational factors
108
 Hostile administrative climate
 Hostile management attitude
 Poor interpersonal relationship
 Lack of worker participation in decision making
 Authoritarian leadership style
 Lack of economic incentive for better work
 Irresistible sickness insurance

109. d. Societal or external factors
109
 Availability of ample employment opportunities
 Lack of social pressure that discourage staying at
home

110. Prevention of absenteeism
 Good industry management and practices
(humanization)
 Adequate pre-placement examination
 Adequate inter-personal relations
 Application of ergonomics
 Health education
 Of employers
 Of management
 Of workers
110

111. 2. Occupational cramps
111
 Seen in workers engaged in activities involving rapid
repetitive movements of short range requiring
precision and coordination.
 For example those who have to type, write and
operate keyboards.

112. 3. Traumatic neurosis
112
 It occur in workers who suffer an accident in an
emotionally charged environment.
 This usually does not occur after accidents outside
the occupational settings.
 These patients suffer from impaired memory,
concentration & sleep, restlessness and irritability.

113. Occupational accidents and injuries
 Agent, host and environmental factors are involved
 Agent factors:
 Physical
 Chemical
 Mechanical
 Host factors:
 Predisposing personality traits
 Immaturity, inexperience, ignorance, inattentiveness,
overconfidence
 Predisposing age periods
 Too young or too old
113

114.  Predisposing habits
114
 Excessive smoking or alcoholism
 Predisposing diseases
 Physical, mental or psychological origin.
 Environmental factors
 Poor illumination, poor communication, high temperatures,
noise, high humidity levels,
 Unsafe operations, unguarded machine parts
 Hostile work environment, poor management, long working
hours, frequent night shifts, non-availability of personal
protective equipment.

115. Prevention
 Safety education
115
 Knowledge on causation of accidents
 Safe operations of machines and mechanisms
 Use of personal protective equipment
 Engineering control
 Safe designing of machineries, buildings & working areas
 General measures like illumination, ventilation, noise control
& temperature control.
 Administrative control
 Humanization of personal management, elimination of long
working hours, interposition of rest periods, reduction in night
shifts and improvement of comfort facilities.

116. Ergonomics- lecture objective
 By the end of the lecture student should be able to:
 Define ergonomics.
 Name ergonomic related disorders/injuries.
 Recognize and suggest control of occupational ergonomic
hazards.
116

117. Ergonomics
117
 It is the study of men at work
with a view t identify the stress
factors operating in a work
environment and impairing
physical, mental and
psychological health of workers
and interfering with their work
performance.

118. What is Ergonomics?
 “Ergonomics is an applied science concerned
with the design of workplaces, tools, and tasks
that match the physiological, anatomical, and
psychological characteristics and capabilities of
the worker.” Vern Putz-Anderson
 “The Goal of ergonomics is to ‘fit the job to the
person,’ rather than making the person fit the
job.” Ergotech
 “If it hurts when you are doing something, don’t
do it.” Bill Black

119. Why do we care about
Ergonomics?

120. Types of Injuries
• Muscle pain
• Joint pain
• Swelling
• Numbness
• Restricted motion
• Repetitive stress injury
• Repetitive motion
injury
• Cumulative trauma
disorder
• Musculoskeletal
disorder

121. Target Regions
• Back
• Upper extremities
• Lower extremities

122. Multidisciplinary study
 Anatomy and Physiology
 Psychology
 Anthropology
 Epidemiology
 Engineering
 Engineering Psychology
 Medicine
 Biomechanics
122

123. Applied to..
 Originated from defense sectors of US & UK.
 From there it moved on to
 Mining
 Forestry
 Agriculture
 Now it has expanded to
 Schools & colleges
 Offices
 Laboratories
 Workshops
 Business centers
 Research centers
123

124. Occupational stress
 Work stress
 Monotonous work, shift work,
uneven work, static work, dynamic
work
 Worker’s stress
 Worker mismatch
 Anthropometric mismatch: male/female, various age groups
 Physical mismatch: muscular strength and work demand
 Sensory mismatch: visual acuity and hearing
 Cognitive mismatch: ability to process and interpret information
 Awkward posturing
 Poor work station layout
124

125.  Role at work
125
 Ambiguity or conflict in role at work
 Environmental stress
 Physical stressors
 Poor ventilation, poor illumination,
high intensity noise, extremes of temperatures
 Social stresses
 Poor social relationships
 Impersonal and inhumane management
 Migration stress
 Language barrier, culture barrier, change of climate, separation
from families, discriminatory attitude of management.

126. Ergonomic solutions
 Ergonomic designing
 Application of human factor engineering in designing
workstations, furniture items, machine components, and hand
tools.
 Ergonomic environment
 Physical ergonomics
 Temperature control
 Noise control
 Illumination sources
 Adequate ventilation
 Cognitive ergonmics
126

127.  Organizational ergonomics;Worker friendly management
policy
 Appropriate worker placement
 Appropriate work distribution
 Appropriate worker rotation
 Worker welfare
 Canteen facility
 Restrooms, change rooms
 Drinking water points
 Toilets
 Crèches
 First aid facility
127

128. Benefits of Ergonomics
• Decreased injury risk
• Increased productivity
• Decreased mistakes/rework
• Increased efficiency
• Decreased lost work days
• Decreased turnover
• Improved morale

129. Health and welfare of industrial
worker
129
1 . MEDICAL MEASURES

130. 1. Medical measures
 Serial health check-ups
 Pre employment
 Pre placement
 Periodical
130
 Comprehensive health care
 Medical care facility
 First aid care boxes; duly equipped and regularly updated,
rehabilitation of disabled workers,
 Public health service
 Immunization, disinfection, personal protection, environmental
control and chemotherapy, MCH services, health education.

131. 2. Engineering measures
 Controlling the source
 Substitution
131
 Replacing harmful agent or process by a harmless agent or
process.
 Scope is limited to the availability of the alternative.
 Examples include
 Lead paint with zinc or iron paints
 Mercury salts with silver salts
 Safer asbestos varieties
 Dry sweeping with wet sweeping
 Dry drilling with wet drilling

132.  Isolation
132
 Segregation of a hazardous material or process by interposing
barriers or increasing the intervening distance.
 Examples include:
 Enclosing a harmful material in a leakproof container.
 Releasing of contaminants (dusts & fumes) in an enclosure and
releasing them by exhaust ventilation.
 Noise proof enclosures
 Restriction of hazardous processes to night shifts only.
 Local exhaust ventilation
 It is an engineering mechanism for trapping the hazardous
material or dust at its origin and disposing it off by negative
pressure.

133.  Controlling the environment
 General ventilation
 Thermal comfort
 General illumination
 Protecting the worker
 Light and well fitting helmets
 Goggles, eye shields or visors
 Ear plugs or ear muffs
 Mask or breathing apparatus
 Liquid proof suits or gas proof suits, cold jackets, lead sheets
and reflectors for radiation or temperature hazards.
 Gloves and gumboots
133

134. 3. Supportive measures
 Administrative support
134
 Worker friendly Management policy
 To create congenial work environment, raise morale of the
workers, increase their job satisfaction, improve their work
performance & increase their work output.
 Job rotation
 For regulating worker exposure to hazardous agents
 Housekeeping
 Attention to cleanliness, illumination, ventilation, provision of
eating, washing and waste disposal facilities, regular mopping and
vacuum cleaning of all the passage ways, stair ways and working
stations, continuous removal of dust and debri, egular coating of
walls, windows and ceilings, dusting of furniture, machines,
rafters, beams etc,
 Keeping everything in its allotted place

135. 135
 Monitoring and surveillance
 Periodic inspection and assessment of factory environment
 Samples of blood, urine, exhaled air, saliva, hair and nails are
collected from workers and analyzed.
 Training and research
 To familiarize the workers with working environment, agents
which might be hazardous, personal protective equipment and
their use.
 Research to find out solutions to industrial problems, to
determine permissible levels of various contaminants, to
standardize various operations to render them safe and
develop appropriate measures for better control of
occupational hazards.

136.  Legal provisions
 The factories act
136
 Employment provision; age, hrs of work, leave entitlement
 Welfare provision; washing points, rest rooms, lunch rooms,
sitting areas, Crèches, first aid boxes
 Sanitary provisions; latrines, urinals, drinking water points, waste
disposal arrangements
 Safety provisions; Enclosure and fencing of dangerous machines,
safety exits
 The employees insurance
 Medical benefit
 Comprehensive medical care, including outpatient, inpatient,
domiciliary investigational and MCH services

137.  Sickness benefit
 Periodic payment to workers disabled due to employment injury
 Maternity benefit
 Maternity leave, provision of Crèches,
 Dependant benefit
 Payable to widows and children under 18 years of age.
 Funeral expenses
137

138. 138