04. CHAPTER - 4 Accident Caution Theory

CHAPTER - 4

Accident Causation and Prevention
THEME

1.
2.
3.
4.

Causation or Occurrence ?
The Accident Problem
Need for Safety
Reasons for Accident Prevention
4.1 Humanitarian or Basic Need
for Safety
4.2 Economic or Costs of accident
4.3 Social
4.4 Legal
4.5 Productivity.
5. Factors Impeding Safety
5.1 At the Management level
5.2 At the Workers level
5.3 At the Government level
6. Basic Terms in Accident
Prevention
6.1 Incident
6.2 Accident
6.3 Injury
6.4 Dangerous Occurrences
6.5 Dangerous Operations
6.6 Hazardous Processes
6.7 Occupational (Notifiable)
Diseases

7.

7.2 Frank Bird’s Updated Domino
Theory
7.3 Hepburn’s Theory
7.4 Multiple Causation Theory
7.5 Systems Model Theory
7.6 Ferrell’s Human Factors
Theory
7.7 Peterson’s Accident-Incident
Causation Theory
7.8 Epidemiological Theory
7.9 Surry’s Decision Theory
7.10Energy (Release) Theory
8.

Principles of Accident Prevention
8.1 Types of Accidents
8.2 Fundamentals of Accident
Prevention
8.2.1 Organisation
8.2.2 Fact Finding
8.2.3 Analysis of the Facts
8.2.4 Selection of Remedy
8.2.5 Application of Remedy
8.3 Models for Accident Prevention
8.4 Five
‘E’s
of
Accident
Prevention
8.5 Approaches
to
Preventive
Action

Theories of Accident Causation
7.1 Heinrich’s Theory

1. CAUSATION OR
OCCURRENCE ?

The word ‘causation’ points out ‘our
responsibility’ and suggests the positive
preventive measures to remove real
reasons causing that accident. The word
‘occurrence’ points out occurring by
chance or fate or something else and
indicates nobody’s responsibility, which is
not the healthy or safe philosophy of
safety.
IS:3786 gives seven factors relating
to causation of accidents : agency, unsafe
mechanical or physical condition, unsafe
act, unsafe personal factor, type of
accident, nature of injury and location of
injury.
The terminology and philosophy given
in Chapter 2 and 3 must be studied
before reading any chapter including this
one.

The term Accident Causation is
preferred against ‘Accident Occurrence’
because of the safety philosophy that
‘Accidents do not occur, they are caused’.
Most of the accidents are caused by
our latent or patent, visible or invisible,
known or unknown, detectable or
undetectable, intentional or unintentional
unsafe acts, conditions and sequential
events leading ultimately to accident.
They explain rather the causation and
not just the occurrence. Therefore all
safety people should analyse this
causation to find out the appropriate
measures for prevention.

1

2 THE ACCIDENT PROBLEM

5 to discuss its various aspects. Yet, some
highlights are given below:
In India during 1994 there were total
190435 accidental deaths recorded, out
of which the figure in factories was 606
(For other causes see tables in Chapter5). Total injuries (fatal and non-fatal
accidents) during 1982 and 1983 were
296027 and 213160 respectively. This
figure in 1990 and 1991 was 128117 and
60599
respectively.
This
indicates
decrease in accidents despite increasing
industrialisation and employment. This is
owing to non-reporting of accidents from
many states. See Part-2 of Chapter-5 for
such inadequacy of data. Yearly @6000
fatal and 6 lakhs reportable injuries are
estimated in factories of our country.
The accident-tall in factories of the
Gujarat State is also given in Tables of
Chapter-5.
Similarly
figures
for
accident
compensation and expenditure can be
obtained from all insurance companies,
ESIC authorities, hospitals, dispensaries
and other sources to understand the
accident problem from all sides. Some 30
crores rupees are estimated as national
cost of injuries per year.
The accidents are classified industrywise
and
causation-wise.
Such
classification and breakup are explained
in Chapter-5.
Besides human injuries, there are
property damage (no injury) accidents,
which are 10 to 20 times higher than the
first-aid accidents.
Non-reporting and under reporting of
accidents
(including
occupational
diseases), make this problem more
severe.
The accident problem emphasises the
need for safety and accident prevention
techniques, which are discussed below.

The zero accident goal is an ideal
goal, and one must try to achieve it by
using
all
safety
philosophy
and
technology. In reality, an industry and
accidents are co-related and each
industry is facing the accident problem,
the number and magnitude may be
varying.

Nature
and
Problem:

Size

of

the

It is this accident problem at the root
which has generated the need of safety.
Deaths, injuries and suffering are its
direct results. Compensation, productionloss, time-loss and various costs-loss are
indirect results. The injured worker, his
family, factory and the nation, all are the
sufferers. Accidents not resulting in
human injuries, but resulting in property
damage
or
money-loss
are
also
accountable and undesired. Therefore
accident is always undesirable. That is
why
the
accident
problem
has
attracted attention worldwide.
Many employers look to it leniently
and do not pay proper attention. They
feel that it is cheaper to prolong the
hazard than to remove it. Because of the
insurance schemes and ESI Act, many
employers think that now they should not
worry because they have insured their
plants and workers against accident and
they will be compensated. Such attitude
increases the accident-problem and acts
against the efforts for safety.
Many workers also tend to take
advantage of the ESI Scheme and invite
unnecessary
accidents.
This
has
increased the number of reportable
accidents, which can be reduced by the
motivation of workers and their unions.
The national money-loss and time-loss by
such accidents must be prevented by coordinated efforts. Training at all levels
help much in this regard.
The size (severity) of this accident
problem can be judged from the (1) Cost
of the accidents and (2) Statistics of
accidents which are explained in Chapter-

3 NEED FOR SAFETY
Much is said and can be said for the
need of safety. Everybody recognises its
need. A few factors are given below:
1. Industries are increasing to fulfil basic
human needs and requirements of
goods, services and facilities. This

2

brings industrial hazards of various
types viz. mechanical, electrical,
noise,
vibration,
chemical
(fire,
explosion, radiation, gas, dust, fumes,
poisoning etc.) and many visible or
invisible health hazards. It is the basic
need to protect the human life and
environment from all such hazards.
Only safety can do it.
2. Direct and indirect costs of accidents
are tremendously increasing and
causing the great national loss. This
can be prevented by safety (see part
4, Chapter – 5).
3. Workers are our national wealth. We
cannot afford to lose them. Fatal
accidents must be minimised to
prevent this fatal loss.
4. Deaths and injuries extend suffering
to the families and society also. This
must be prevented or curtailed by
safety.
5. Social loss in the form of pain, loss of
earning capacity, loss of life or limb,
ill-effects to health, diseases, increase
of handicapped persons, increase of
court cases and emotional losses due
to accidents must be reduced by safe
conditions, safe practices and training
for them.
6. Productivity is linked with safety.
Increasing and maintaining safety
gives good productivity.
7. Humanitarian,
legal,
social
and
economic
reasons
for
accident
prevention are also true for the need
of safety. They are explained below.
Based on above requirement, it can
be said that ‘as place of industry in
society is inevitable, place of safety in
industry is also inevitable. As industry is
useful to society, safety is useful to
industry.

Accident
Prevention
4
Legal

Fig. 4.1 :
Prevention

Reasons

for

Accident

4.1
Humanitarian or Basic
Need for Safety:
The vedic philosophy that a man
should protect man is the fundamental or
basic reason for accident prevention.
Employers should protect their workers by
providing good working conditions, safety
equipment and training. It is their
humanitarian or moral or basic duty
under the common law. Similarly the
employees
should
also
protect
themselves and their fellow employees
and surrounding, by their safety duty,
precautions and safe practices. Protection
of self and others is the primary duty of
every person from humanitarian point of
view. Our Hindu culture thinks of
protection of birds, animals and all living
creature
far
beyond
the
human
protection.
To minimise deaths and injuries, pain
and social suffering is the basic need for
accident prevention.
For any industrial activity five ‘M’s
are requiredMoney,
Material (includes machinery),
Manpower,
Management, and
Market.
Out of these, only manpower is a live
element and others are dead, functional
and operated by men. All other factors
are for men only. Management and
market cannot function without men.
Money and material cannot flow without
men. Machinery cannot be designed,
operated and maintained without men.
Thus ‘man’ is predominant and most
important factor in all-industrial activities.
Prevention of accident to ‘man’ is
therefore most essential.

4 REASONS FOR ACCIDENT
PREVENTION
Five main reasons for accident
prevention are stated below and shown in
Fig. 4.1.
1
Humanitarian
5
Productivity

3
Social

2
Economic

3

4.2
Economic
Accidents:

or

Costs

for breach of certain safety provisions
resulting in death or serious bodily injury.
Enhanced penalty is prescribed for
repeated offence. The court can pass an
order for compliance also. The inspector
has power to issue an order to require
safety measures before a specified date
or to prohibit to run the factory till the
compliance is carried out. Thus legal
reason for accident prevention is strictly
set out for the employers, and is
supported by the Courts’ judgements.
The statutory duty is imposed upon
employees also to observe safety rules,
maintain safety guards and conditions,
and to use safety equipment so as not to
injure self and others.
In democracy, everybody suppose to
know and follow the law of the land.

of

There are three agencies that suffer
economic losses due to accidents:
1 Worker and his family.
2 Management.
3 Society and nation.
Worker & his family suffer economic
losses due to loss of life or limb, loss of
earning capacity and extra expenses viz.
medical,
nutrition,
transport
etc.
Emotional and mental suffering is extra
loss.
Management sustains money loss
due to direct (insured) and indirect
(uninsured) costs of accidents (For details
see Part 4 of Chapter-5). The above costs
added together give the total cost to the
organisation.
The
top
management
should consider cost benefit analysis and
adopt cost effective safety measures to
reduce such costs, pain and suffering.
Accident cost should not be compared
with the benefit (cost benefit ratio) to the
company. Investment for safety should be
considered always necessary.

4.3

4.5

‘Safety increases productivity,’ needs
to be understood.
Peter Drucker defines productivity as
“the balance between all factors of
production that will give the greatest
output for the smallest effort”. It is
maximum when highest output is
obtained with minimum expenses of
resources and when resources are not
used in the most economical manner.
Productivity requires elimination of
loss in all forms viz. losses of men,
materials,
machine,
manufacturing
process, products, money, time etc. It
covers many factors from design to
disposal level. Safety maintenance for
accident prevention reduces such losses,
cuts accident costs and helps directly in
increasing productivity. The employers
must recognise this fact and must invest
sufficient money for accident prevention
and reduction programmes, which will
save money, time and injury losses due
to
accidents
and
increase
their
productivity and profit.
Thus a safe way is the best way and
safety is a key to productivity. It is also
said that safety and productivity go hand
in hand or they are two sides of a coin.
Thus safety and productivity are
equally important and help each other.
However
in
practice,
many
times

Social:

Society is benefited by help from the
men and goods, services and production
from the men.
Injury or death of a worker is not an
individual loss but directly and indirectly it
is a loss to the society also because a
man does not live in isolation. He is
connected with society and has many
relations in many directions. Therefore
loss of a person is loss to the society by
way of his usefulness to the society.

4.4

Productivity:

Legal:

Legal reasons for accident prevention
are due to laws framed by the
Government.
It is the statutory duty of occupiers
under the Factories Act 1948 and other
Acts to provide safe conditions for the
prevention of accidents and protection of
workers. Breach of law may result in
prosecution,
fine,
punishment
and
adverse publicity. Heavy penalty and
compulsory imprisonment are provided

4

production people consider safety as an
obstruction or brake to their work and
require workers to go ahead by any
means to meet production target. Such
attitude may result in accident which will
retard productivity.
By
definition
‘accident’
means
interruption or interference with the
orderly progress or production (see part
3.1, Chapter –2). Then how can an
accident prevention work or safety be
considered
against
productivity?
Therefore this wrong belief of ‘safety
against productivity’ must be corrected as
‘safe production is the only production’.
One report says that a safe factory is 11
times more productive than an unsafe
factory.
Safety and productivity both are
affected
if
housekeeping,
working
conditions,
procedures,
supervision,
training, preventive maintenance etc. are
poor and both can be improved by
improving these common factors.

6. Improper location and layout of plant,
building, machinery and equipment.
7. Improper design or selection of tools,
machines,
materials,
vessels,
equipment and products.
8. Improper methods, procedures or use
of
raw
materials,
machines,
equipment etc. in storage and
manufacturing process.
9. Lack of inspection, supervision and
training for safety.
10. Absence of safety organisation for
proper and continuous attention on
safety.
11. Lack of awareness and insistence for
safety.
12. Improper selection or placement of
men, machines, methods, tools,
equipment etc.
13. Lack of motivation and participation
for safety.
14. Poor infrastructure of the organisation.
15. Poor financial
condition of the
organisation or not providing sufficient
safety budget.
16. No written rules for job description,
procedure and safe production.
17. Lack of safety aspects in accident
prevention.
18. Frequent changes in shifts, working
hours and calling workers for overtime
work or on holiday etc.

5 FACTORS IMPEDING
SAFETY
The factors impeding i.e. retarding or
injuring safety are those factors, which go
against the efforts for safety. It is
necessary to identify such negative
factors (as they cause hazards) and to
remove them for the purpose of safety.
A list of such factors may be very
long and may vary from factory to factory.
Some common factors are classified and
given below:

5.1
At
Level:

the

5.2 At the Workers Level:
1. Passive interest in safety by workers.
No or less participation in safety
programmes
including
safety
committee.
2. Insufficient knowledge, qualification
and training for the job.
3. Reluctant to use PPE and other safety
equipment.
4. Not maintaining the machine guards,
safety devices, records etc.
5. Misuse of guards, safety devices,
protective equipment etc.
6. Indiscipline, laziness, disobedience for
safety rules for whatsoever reasons.
7. Non co-operation to the management
to carry out regular as well as
emergency safety duty for safe close
down or safe running of the plant and
processes to avoid accidents.

Management

1. Passive interest in safety by the
management. No safety policy.
2. Compromising safety for production.
3. Poor maintenance of machines and
equipment.
4. Poor working conditions or not
providing
proper
lighting
and
ventilation, safety guards, devices
and equipment.
5. Ageing of the machines, plant and
buildings.

5

8. Guided by personal (psychological)
factors causing unsafe actions.
9. Poor socio-economic status, financial
hardship, family problems, feeling of
injustice, worries, tensions etc.
10. Improper attention or judgement on
the matters of safety.

The term physical harm in above
definition includes injury, death, disease
and adverse mental, neurological or
systemic effects resulting from an
exposure or circumstances encountered
in the course of employment.
Heinrich’s definition of an accident is
“An unplanned and uncontrolled event in
which the action or reaction of an object,
substance, person, or radiation results in
personal injury or the probability thereof”.
Like
a
mathematical
theorem
he
concludes:

5.3 At the Government Level:
1. Not enacting or amending requisite
safety laws and poor or nonimplementation of the enacted safety
laws.
2. Poor or no incentives, awards,
rewards,
programmes,
subsidy,
rebates,
text
benefits
and
encouragement to employers and
employees for their safety efforts.

1. A personal injury occurs only as the
result of an accident.
2. An accident occurs only as the result
of a personal or mechanical hazard.
3. Personal and mechanical hazards
exist only because of the faults of
persons.
4. Faults of persons are inherited or
acquired by environment.

6 BASIC TERMS IN
ACCIDENT PREVENTION
See Part 3 “Safety Terminology” of
Chapter-2 for the definitions of terms. The
words - accident, accident prevention,
damage, danger, hazard, loss control and
prevention, risk, safety, unsafe act,
unsafe conditions, system safety etc., are
defined therein.

This theorem points out personal
fault (unsafe act) as the root of any
accident.
A
person
designs,
manufacturers, operates and maintains a
machine, equipment, plant etc. His fault
(error or mistake) lying anywhere from
design stage to maintenance stage may
cause an accident which results in injury.
An ‘accident’ is also defined as “An
unplanned and unexpected event which
causes or is likely to cause an injury”.
An ‘accident’ is the result of
carelessness, casualness or any fault
known or unknown. This points out that
carelessness and casualness (taking thing
lightly) or any hidden fault can cause an
accident.
Sachman defined in 1961, accident
as an event which is unexpected,
unavoidable and unintended. However
other researchers of accident causation
analysis say that most of the accidents
are avoidable or preventable. This
concept emphasises the need and
importance of control technology to
minimise the accidents.
‘Accident’ as defined by ‘Accident
Facts, NSC, USA’ in their 1997 edition, is
that occurrence in a sequence of events
which produces unintended injury, death
or property damage. Accident refers to

The basic terms directly connected
with accident causation are discussed
below:

6.1

Incident:

See part 3.43, Chapter –2 for
definition.
Incident may be good or bed. For
accident phenomenon, it indicates event
that results in accident.

6.2

Accident:

It is an undesired or unintentional
event that results in physical harm to a
person or damage to property or
environment. It is usually the result of a
contact with a source of energy (kinetic,
electrical, thermal, chemical, radiation)
above the threshold limit of the body or
structure.

6

the event, not the result of the event,
while unintentional injury refers to the
result of an accident and is the preferred
term for accidental injury.
It is also defined as “An unplanned or
unintended occurrence that interrupts or
interferes with a work activity”.
This
definition is based on the fact that many
accidents, the great majority, yield no
injury and receive passing attention only.
Thus there may or may not be any
injury to person or property, the only
symptom of an accident is ‘interruption or
interference with a work activity or
energy transfer’. This is the broad
definition, giving rise to the concepts of
‘Damage accident’, ‘Lost-time accident’,
‘Total loss control’ and ‘Total loss
prevention’.
Nowadays we see ‘planned or
intended accident’ also, but, then they
may fall under the Indian Penal Code as
offences against person or property.
Traditionally, in industry, an accident
is considered as an unplanned or
unexpected event resulting in injury to a
person or property or both. Damage
accidents (without human injury) have
not received due attention in the accident
prevention programmes. Statutorily some
damage
accidents
(dangerous
occurrences) are reportable under the
Factories Act, 1948.
The word ‘accident’ as defined by
Indian Standard: 3786 - 1983 means an
unintended occurrence arising out of and
in the course of employment of a person
resulting in injury.
For the purposes of the Workmen’s
Compensation Act 1923, ‘a personal
injury caused to a workman by accident
arising out of and in course of his
employment’
is
said
eligible
for
compensation depending upon the types
of injuries listed in Schedule-I and the
occupational diseases in Schedule-III of
the Act.
The word accident is not defined in
the Factories Act. Its reporting is defined
as follows (Section 88).
Notice of certain accident: where
in any factory an accident occurs which
causes death, or which causes any bodily
injury by reason of which the person
injured is prevented from working for a

period of forty-eight hours or more
immediately following the accident, or
which is of such nature as may be
prescribed in this behalf, the manager of
the factory shall send notice thereof to
such authorities, and in such form and
within such time, as may be prescribed.
Report of accident to a person or
animal is also required under the
Electricity Act and Rules.
Thus the pure or theoretical definition
of ‘Accident’ includes ‘event’ but not
necessarily its result as injury or damage.
In this context, it is as good as ‘near-miss’
and accident may or may not have injury.
The legal or practical definition of
‘accident’ includes both ‘event’ and
‘injury’ otherwise it is not an accident.
Above matters are prescribed under
Rule 103 of the Gujarat Factories Rules,
which
also
prescribes
‘dangerous
occurrences’ which may or may not
include personal injury.
For further discussion see part 3.1 of
Chapter –2.
An
accident
sequence
and
consequence are explained in part 7.1
following.

6.3

Injury:

To injure means ‘to hurt’ and an injury
means ‘a harm’. In legal terms injury may
be to a person or property or both and
compensation (damages) can be awarded
to the injured person for the loss he has
suffered and may continue to suffer.
Punitive damages can be awarded for
grave injury.
An injury could be psychological
also and not necessarily a physical
condition resulting from a mechanical,
electrical,
chemical
or
radiological
accident. A heart attack resulted from
unusual mental stress from the work is
injury for which compensation is payable.
But natural death or heart attack during
normal activities may not be considered
as an injury from accident.
Injuries are not considered resulting
from an accident where wilful death, selfinflicted intentional injury, intoxication
and undue alteration by the person
injured are involved.

7

There

are

two

types

of

injuries.

depends upon the material causing injury,
energy released, body part being injured
and the physical or mental condition of
the person being injured. As accident
precedes injury, attention should be paid
to prevent the accident.
H.W. Heinrich estimates that in a unit
group of 330 accidents of the same kind
and
involving
the
same
person,
considering average of averages, 300
result in no injuries, 29 in minor injuries
and 1 in a major lost-time injury. It
indicates an ample opportunity to
prevent any injury by efforts during 300
no-injury or warning accidents. This
foundation of a major injury is shown in
Fig. 4.2.

Major Injury
1

Minor injuries

29
300

No injury
accidents

Minor injury generally means that
having no permanent effect and leading
to less than three days off work. Major
injury generally means that leading to
more than three days off work. The major
injury may be fatal (death) or serious. A
fatal injury is a great loss to the family
and society.
An injury is an external damage to
the
human
body,
disturbance
or
dysfunction resulted from an accident.
By
cause,
injuries
may
be
mechanical (bruise, cuts, tissue ruptures,
breakage etc.), thermal (shock, burn,
frost-bite),
chemical
(burn,
acute
intoxication and poisoning), radiated
(tissue regeneration, changes in the
haematopoietic system), or combined
(the effect of more than one causative
factor with various consequences). The
result of accidents (which may cause
serious, minor or no injury) may be the
causes of temporary or permanent
disablement or a fatality.
The
term
“accidental
injury”
denotes an injury to a workman due to an
accident. It does not include an injury to a
worker’s health unless it results directly
from an accident, as for example, a
poisoning due to toxic chemical.
“Serious bodily injury” as defined
in section 92 of the Factories Act means
“An injury which involves, or in all
probability will involve, the permanent
loss of the use of, or permanent injury to,
any limb or the permanent loss of, or
injury to, sight or hearing, or the fracture
of any bone, but shall not include, the
fracture of bone or joint (not being
fracture of more than one bone or joint) of
any phalanxes of the hand or foot”.
An injury is merely the result of an
accident. An accident is controllable, but,
when it occurs, it is difficult to control the
resulting injury. The severity of accident

Fig. 4.2 : Foundation of a major
injury
See Part 7.1 for further discussion on
this ratio theory.

6.4

Dangerous Occurrences:

U/s 88A of the Factories Act and u/r
103 of the Gujarat Factories Rules, the
following occurrences are prescribed as
dangerous and they are reportable in
Form No. 21 (for bodily injury or death) &
21A (for no bodily injury, property
damage may or may not be resulted):1. Bursting of a steam plant under
pressure.
2. Collapse or failure of lifting appliances
or overturning of a crane.
3. Fire, explosion, escape of molten
metal, hot liquor, gas etc.
4. Explosion of a pressure vessel.
5. Collapse or subsidence of a structure.

6.5

Dangerous Operations:

The term ‘dangerous operation’ is
used in section 87 of the Factories Act
meaning ‘Any manufacturing process or
operation carried on in a factory exposing
any person employed in it to a serious
risk of bodily injury, poisoning or disease’

8

and the State Government is advised to
make
rules
regarding
dangerous
operations.
Rule 102 of the Gujarat Factories
Rules lists 27 Schedules of such
dangerous operations. Their subjects are
briefly mentioned below :

products, waste or effluents thereof would
 cause material impairment to the
health of the persons engaged in or
connected therewith, or
 result in the pollution of the general
environment.

1.
2.
3.
4.
5.
6.
7.
8.
9.

The First Schedule of the Act lists 29
industries of hazardous processes as
under:

Aerated water processes.
Electrolytic plating or oxidation.
Electric accumulators.
Glass manufacture.
Metal grinding or glazing.
Lead and its compounds.
Dangerous petroleum gas.
Blasting operations.
Liming and tanning of raw hides &
skins.
10. Chromic acid and bichromates.
11. Carcinogenic Dye intermediates.
12. Acids or alkalis.
13. Acetone, tetrachloroethane and other
solvents.
14. Carbon disulphide and Hydrogen
sulphide.
15. Dangerous pesticides.
16. Oxygen and Hydrogen compression.
17. Asbestos.
18. Stone or free silica.
19. Chemical works.
20. Benzene and allied products.
21. Solvent extraction plants.
22. Carbon disulphide plants.
23. High Noise.
24. Gas Welding or Cutting.
25. Pottery.
26. Foundries.
27. Cotton dust.
The details of all above schedules
suggest preventive measures for serious
risk of bodily injury, poisoning or
occupational diseases. They must be
thoroughly studied and implemented.

6.6

1. Ferrous Metallurgical.
2. Non-ferrous Metallurgical.
3. Foundries.
4. Coal.
5. Power generating.
6. Pulp and Paper.
7. Fertiliser.
8. Cement.
9. Petroleum.
10. Petrochemical.
11. Drugs and Pharmaceutical.
12. Fermentation.
13. Rubber.
14. Paints and Pigments.
15. Leather tanning.
16. Electroplating.
17. Chemical.
18. Pesticides.
19. Synthetic Resin & Plastics.
20. Man-made Fibre.
21. Electric accumulators.
22. Glass & Ceramics.
23. Metal grinding & glazing.
24. Asbestos.
25. Oils & Fats.
26. Benzene.
27. Carbon Disulphide.
28. Dyes & Dyestuffs.
29. Highly flammable liquids and gases.
The Second Schedule gives TLV and
STEL values of certain chemicals and the
Third Schedule gives a list of occupational
diseases.

Hazardous Processes:

Section 2(cb) of the Factories Act
defines ‘hazardous process’ as follows:
“Hazardous process” means any
process or activity in relation to an
industry specified in the First Schedule
where, unless special care is taken, raw
materials
used
therein
or
the
intermediate or finished products, by-

6.7 Occupational
Diseases:

(Notifiable)

The Third Schedule under Section 89
& 90 of the Factories Act gives a list of 29
notifiable occupational diseases and
poisoning including those due to lead,

9

tetra-ethyl lead, phosphorous, mercury,
manganese, arsenic, nitrous fumes,
carbon bisulphide, benzene, chrome
ulceration, anthrax, silicosis, halogens,
radium or radio active substances or Xrays, skin cancer, toxic anaemia, toxic
jaundice,
oil
acne
or
dermatitis,
byssionosis, asbestosis paint or chemical
dermatitis,
noise,
beryllium,
carbon
monoxide, coal miners’ pneumoconiosis,
phosgene,
occupational
cancer,
isocynates and toxic nephritis.
Schedule III of the Workmen’s
Compensation Act 1923 also gives a list
of 34 occupational diseases in its part A,
B & C. A similar list is also given by the
ESI Act.
Only statutory occupational diseases
are listed above, but, there are many
non-statutory diseases also which need
accident or disease prevention. For
details see Part 7 of Chapter-24.
Thus statutorily it is emphasised that
the
terms
accident,
dangerous
occurrence,
dangerous
operation,
hazardous process and notifiable disease
requires
personal
bodily
injury,
impairment to health or environment i.e.
pollution.
Thus those accidents (including
diseases and poisoning) are given more
attention, which pose injury to a person,
property or environment.

Ten Axioms of Industrial Safety:
1. The occurrence of an injury invariably
results from a completed sequence of
factors - the last one of these being
the accident itself. The accident in turn
is invariably caused or permitted
directly by the unsafe act of a person
and/or a mechanical or physical
hazard.
2. The unsafe acts of persons are
responsible for a majority of accidents.
3. The person who suffers a disabling
injury caused by an unsafe act, in the
average case has had over 300 narrow
escapes from serious injury as a result
of committing the very same unsafe
act (see fig. 4.2). Likewise, persons are
exposed
to
mechanical
hazards
hundreds of times before they suffer
injury.
4. The severity of an injury is largely
fortuitous - the occurrence of the
accident that results in injury is largely
preventable.
5. The four basic motives or reasons for
the occurrence of unsafe acts provide
a guide to the selection of appropriate
corrective
measures.
These
are:
Improper attitude, Lack of knowledge
or skill, Physical unsuitability and
Improper
mechanical
or physical
environment.
6. Four basic methods are available for
preventing
accidents.
These
are
Engineering revision, Persuasion and
appeal, Personnel adjustment and
Discipline.
7. Methods of most value in accident
prevention are analogous with the
methods required for the control of the
quality,
cost
and
quantity
of
production.
8. Management has the best opportunity
and ability to initiate the work of
prevention, therefore it should assume
the responsibility.
9. The supervisor or foreman is the key
man in individual accident prevention.
His application of the art of supervision
for the control of work performance is
the factor of greatest influence in
successful accident prevention. It can
be expressed and taught as a simple

7 THEORIES OF ACCIDENT
CAUSATION
Various theories are developed to
explain the phenomena of accident
causation and prevention. They are
explained below:

7.1

Heinrich’s Theory:

H.W. Heinrich, a pioneer in safety
philosophy, first published his work,
Industrial Accident Prevention, in 1931.
Many of his principles and basic
philosophy of accident causation and
prevention are confirmed by time and
application,
but,
some
are
also
questioned and criticised. His philosophy
is based on his 10 axioms (self evident
truths) as follows.

10

four step formula - Identify the
problem, find and verify the reason for
the existence of the problem, select
the appropriate remedy and apply the
remedy.
10. The
humanitarian
incentive
for
preventing
accidental
injury
is
supplemented
by
two
powerful
economic factors: (1) The safe
establishment is efficiently productive
and the unsafe establishment is
inefficient (2) The direct employer’s
cost
of
industrial
injuries
for
compensation claims and for medical
treatment is about one-fifth of the total
(direct plus indirect) cost which the
employer must pay.

to one another that the fall of the first
domino precipitates the fall of the entire
row. An accident is merely one factor in
the sequence. If this series is interrupted
by the elimination or withdrawal of even
one of the five factors that comprise it,
the injury can possibly be prevented. See
Fig 4.3.

1

1
2
3
4
5

These axioms were the first set of
principles or guidelines ever set before in
industrial safety and it has guided all
safety activity till today. During the
passage of 75 years, some of his axioms
are questioned and disbelieved as truths,
but, most of them are still true and deal
with the important areas of safety, viz.
accident
causation
and
prevention,
reasons of unsafe acts and conditions,
management
control
functions,
responsibility of organisation, costs of
accident, safety and productivity etc.

2

3

4

5

Ancestry & Social environment
Fault of Person
Unsafe act or/and condition
Accident
Injury

Fig. 4.3 : Five Factors in Accident
Sequence
In above dominos, social environment
includes
family
and
surrounding
atmosphere in which a person is born and
brought up. This is the origin or root cause
of behavioural development as per H. W.
Heinrich.
Undesirable traits include unsafe
behaviour, negligence, lack of knowledge,
violent
temper,
nervousness,
recklessness etc.
Unsafe act or conditions are the
results of undesirable traits.
Accident is caused because of unsafe
act or condition or both.
Injury is the result of accident.

Accident Sequence: The five factors
in
accident
occurrence
series
in
chronological order are:
1. Ancestry and social environment.
2. Fault of person.
3. Unsafe act and/or mechanical or
physical hazard.
4. Accident and
5. Injury.
One factor is dependent on another
and one follows because of another, thus
constituting a sequence that may be
compared with a row of dominoes placed
on end and in such alignment in relation

This
suggests
the
steps
management controls as under:

Management Through Supervision
Controls
Human Failure
Knowledge - Attitude - Fitness - Ability

11

of

Which causes or permits
Unsafe Acts
of Persons
(88%)
1

Unsafe Mechanical, Chemical,
Physical Conditions (10%)

Operating without authority
or clearance, failure to
secure or warn.
Operating or working at
unsafe speed.

1

Unguarded, absence of required
guards.

2

3

Making Safety devices
inoperative.

3

4

Using unsafe or defective
equipment, or equipment
unsafely or improperly.
Unsafe loading, placing,
mixing, combining, etc.

4

Taking unsafe position or
posture.
Working on moving or
dangerous equipment.
Distracting, teasing,
abusing, startling horseplay
etc.
Failure to use safe affair or
personal protective
equipment or devices.
Failure to warn co-workers
or to secure equipment.
Improper lifting.

6

Inadequate support or guards,
guards of improper height,
strength, mesh etc.
Defective, rough, sharp,
slippery, decayed, cracked
surfaces etc.
Unsafe design of machines,
tools, plant, equipment or
supplies.
Unsafely arranged, poor
housekeeping, congestion,
blocked exists, etc.
Inadequately lighted, sources of
glare etc.
Inadequately ventilated, impure
air source etc.
Unsafely clothed, no goggles,
gloves or masks, wearing high
heels etc.
Unsafe processes, mechanical,
chemical, electrical, nuclear etc.

Servicing equipment in
motion.
Use of drugs or alcohol.

2

5
6
7
8
9
1
0
1
1
1
2
1
3

5

7
8
9
10

Inadequate warning systems.

11

Fire & Explosion hazards.

12

High noise or vibration.

13

Hazardous dusts, gases, fumes,
vapours etc.

Which cause
Accidents
2% Unpreventable
98% Preventable type
50% Practicably preventable
From other similar studies, Heinrich
concludes that, “all agree in general
that man failure is predominantly the
proximate and direct cause of industrial
accident”.
The Economic Times, Mumbai, of
21-9-97 gave following figures of
Railway accidents:

Year



Failure
of
Railway
Staff
Failure

12

9293
363

9394
358

9495
351

9596
237

9697
249

60

72

76

71

59

of other
persons
Other
causes
TOTAL

101

90

74

88

73

524

520

501

396

381

A study by the Department of
Labour and Industry of the State of
Pennsylvania yielded the following:
3% due to mechanical causes.
2% due to unsafe acts.
95% due to a combination of both
causes.

This supports Heinrich’s conclusion
that human failure is the predominant
cause of accidents. However, this is not
necessarily applicable to all or majority
of the industrial accidents as per other
theories.
To find out rate of human failure,
software “Technique of Human Error
Rate Prediction (THERP)” is available.
See Chapter –19.

The ratio idea had done much harm
and many employers still say, ‘Why
should first of all we spend a lot of
money on only 10% mechanical
causes? We will start after 88%
personal causes are removed by the
employees’. Such concept is damaging.
There are two essentials in every
case of injury - there must be some
degree of hazard and there must also
be faulty behaviour by someone. If the
factor of hazard is properly detected
and eliminated there could be no injury.
Similarly, if behaviour could be made
and kept perfect, the result would be
the same. Both these are the duties of
every management. It must try
collectively to combat the combined
causes of accident and should not
separate the unsafe acts as employee’s
responsibility only. Law always stresses
for employer’s responsibility first. Why?
Because the primary duty and ultimate
control lie with the management to
detect and remove unsafe conditions
and actions both, and to give necessary
training to the workers. This is the only
safe and healthy approach.
Heinrich is aware about the public
debate and criticism of his 88-10-2%
ratio in accident causation stated above
and
its
dissemination
that
may
influence people to ignore the machine
guarding and to take the assumedly
easier path of issuing instructions. In
reply, he states his belief that the
accident-prevention
fraternity,
like
almost all professional groups, want all
the pertinent facts and he has more
faith in their good judgement than to
fear that they will ignore the very first
common-sense step of safeguarding
mechanical environment. The machine
is dangerous as man makes it so. It’s
man’s use of the machine - more

Criticism of Heinrich’s Theory
and His Reply:
H.W. Heinrich’s ratio theory (fact
finding from a study of 75000 accident
cases) that 88% accidents are due to
unsafe acts, 10% due to unsafe
conditions and 2% unpreventable is
criticised as follows:
Heinrich made his analysis from
reports submitted to insurers by the
managers of the companies at which
the accidents happened. No manager
would want to indicate to the insurer or
to the safety authority or agency that
the company had been at fault and that
hazards existed in the workplace under
his control. Such a statement may
sound harsh but is borne by known
practices, which also distort statistical
data.
This ratio idea is fallacious because
it rests on a false assumption that
accidents are result of either unsafe
acts or unsafe conditions. Actually there
are multiple (combined) factors as
supported by the results stated below.
A study conducted by the National
Safety Council (USA) yielded the
following conclusions:
18% injuries due to mechanical
causes.
19% injuries due to personal
causes.
63% due to a combination of both
causes.

13

correctly, his abuse of it - that creates
danger.
He points out that judgement must
be used in selecting the major cause
when a mechanical hazard and an
unsafe act both contribute to accident
occurrence. Personal judgement may
lead to error, but it is defensible and in
the majority of cases results in fair
conclusions.

unplanned
event
involving
the
movement of a person or an object,
ray, or substance (slip, fall, flying
object, inhalation etc.), having the
probability of causing personal injury or
property damage but not resulted in
injury (near miss).
Safety and Productivity - Citing
the study made by the Committee on
Safety and Production of the American
Engineering
Council,
Heinrich
has
narrated the detail findings some of
which are given below :

The 300-29-1 Ratio (Foundation
of lost-time accident - Explaining the
foundation of a major injury, Heinrich
estimates that in a unit group of 330
accidents of the same kind and
involving the same person, 300 result in
no injuries, 29 in minor injuries and 1 in
a major lost-time injury. See Fig. 4.2. He
explains this 300-29-1 ratio as an aid in
accident prevention, because, it vividly
emphasises preventive opportunity,
when an employee, either because of
his repeated unsafe action or repeated
exposure to an unsafe mechanical
condition,
suffers
300
no-injury
accidents (actual events such as slips
and falls but fortunately not causing
injury) surely there can be no lack of
opportunity in preventive effort.
Replying
misunderstanding
and
misquotation of this ratio, he states
that this ratio is an average. Sometimes
a major or serious injury occurs the
very first time a person acts unsafely or
is exposed to mechanical hazard - in
other cases he is so endangered
hundreds or thousands of times and
may slip or fall many times before
injury is sustained. In industry, where
employees are under supervision, these
unsafe practices, conditions and the
resulting narrow escapes from actual
injury (events-accidents) are tangible
and visible. They can and should be
controlled long before one of the 300
no-injury accidents ultimately causes
an injury.
In above ratio - cases, a major
injury is any case that is reported to
insurance office or to the State
Compensation Commissioner. A minor
injury is a scratch, bruise, or laceration
such as is commonly termed a first-aid
case. A no-injury accident is an

1. Industrial accidents can be controlled
under modern conditions of highly
efficient productivity.
2. Efforts
to
improve
safety
performance do not interfere with
production.
3. Maximum productivity is ordinarily
secured only when
performance
tends
irreducible minimum.

the accident
toward
the

4. The cost of accidents is a loss in
industrial operation, which should
not be neglected.

7.2
Frank
Theory

Bird’s

Domino

Heinrich’s
theory
of
domino
sequence is updated by Frank Bird Jr. to
explain the circumstances that lead to
losses (injury) in the chronological order
of five dominoes:
These are shown in Fig. 4.4 and
explained below.

1

1.
2.
3.
4.
5.

14

2

3

4

Lack of control - Management.
Basic causes - Origins.
Immediate causes - Symptoms.
Accident - Contact, and
Injury/damage - Loss.

5

Fig.

4.4 : Frank
Sequence

Bird’s

case of property damage and fire
control devices and trained personnel.
Frank E Bird, in 1969, analysed
1753498 accidents reported by 297
companies of America. His conclusion is
shown in Fig. 4.5.

Domino

Lack of control is the first domino
and refers the fourth function of the
management
(planning,
organising,
directing, controlling and coordinating).
It involves accident investigation,
facility
inspection,
job
analysis,
personal communication, selection and
training, ‘standards’ in each work
activity
identified,
measuring
performance
by
standards
and
correcting performance by improving
the existing programmes. This first
domino may fall due to inadequate
standards, programmes and follow up.
Basic Causes (Etiology) are (1)
Personal factors - lack of knowledge or
skill, improper motivation and physical
or mental problems and (2) Job factors inadequate work standards, design,
maintenance, purchasing standards,
abnormal usage etc. These basic
causes are origin of substandard acts
and conditions and failure to identify
them permits the second domino to fall,
which initiates the possibility of further
chain reaction.
Immediate
causes
are
only
symptoms of the underlying problem.
They are substandard practices or
conditions (known as unsafe acts and
unsafe conditions) that could cause the
fourth domino to fall. These causes
should be identified, classified and
removed by appropriate measures.
Accident or incident is the result of
unsafe acts or/and unsafe conditions.
This point is the contact stage. Some
counter
measures
employed
are
deflection,
dilution,
reinforcement,
surface
modification,
segregation,
barricading,
protection,
absorption,
shielding etc.
Injury includes traumatic injury,
diseases
and
adverse
mental
neurological
or
systemic
effects
resulting from workplace exposures.
‘Damage’ includes all types of property
damage including fire. The severity of
losses involving physical harm and
property damage can be minimised by
prompt reparative action, salvage in the

1
10
30
600

Serious or disabling
Injury
Minor injuries
Property damage
accidents
Incidents with no
visible injury or
damage

Fig. 4.5 : The Bird’s accident ratio
study
Inference of this 1-10-30-600 ratio
is that 630 no-injury accidents, with 10
minor and 1 major (serious) injury
accidents, provide a much larger basis
for many opportunities to prevent any
injury accident. Out of total 641 events,
only 10 may result in minor injuries and
only 1 in major injury. But this can
happen at any time not necessarily at
the end.

7.3

Hepburn’s Theory

H.A. Hepburn amplified the above
Heinrich’s theory and arrived at the
principle that an injury accident is the
result of the convergence at the same
point of time of 4 factors (1) Unsafe
actionable (2) Unsafe conditional (3)
Proximate casual and (4) Personal.

Unsafe Actionable
Personal


Accident


Proximate casual



Unsafe
conditional

Here
unsafe
actionable
and
conditional factors are as usual.
Personal factor means person injured or
likely to be injured by an accident and
the person causing the accident. The
proximate factor is that immediate
causative factor such as failure of a
brake, sudden exposure to gas etc.,

15

which by its reaction causes a sudden
closing together or convergence of all
the four factors to cause an injury
accident. He emphasises that the four
factors are complementary to one
another in causation of any injuryaccident such that, if any one or more
can be withdrawn by any means during
or just before convergence, an injuryaccident can be prevented. The event
of an accident will not be prevented by
endeavours to perfect any one of the
factors to the exclusion of the others.
Remedial measures must be adopted
for each of the factors. Like Heinrich he
also suggested planning and organising
to prevent unsafe actions and remove
unsafe
mechanical
or
physical
conditions.

7.4 V.L. Grose’s
Causation Theory:

4. Management means within which
above three parameters operate i.e.
to
be
controlled
by
the
management.
Characteristics of –
1. Man
includes- age, sex, height,
skill level, training, motivation etc.
2. Machine includes- size, weight,
speed, shape, MOC, energy etc.
3. Media
includespressure,
temperature,
content,
contaminants, obstruction on road
etc.
4. Management includes- structure,
style,
policy,
procedure,
communication etc.
Simple example of this theory is a
man slipping due to walking on a
banana skin lying on the road. Here
main contributing factors are as under:
Man – A man walking on the road.
Machine or object or vehicle –
Banana skin.
Media – Slippery skin on hard road.
All above causes are interacting
with each other to lead to the accident.
Absence of any reason can avoid the
accident. This indicates that slippery
banana skin should be removed from
the road or man should be more
attentive for not walking on it or the
road should not be so hard to cause
slipping.
Let us take another example of a
worker falling from a ladder. As per the
domino theory an investigation is as
under :

Multiple

As
per
this
theory
many
contributing factors combine together in
random fashion, causing accidents.
Such factors should be identified. As
shown in figure 4.6, mostly man,
machine and media interact with each
other to generate causes for accident
and management has to identify them
and
provide
necessary
safety
measures.
MANAGEMENT

MAN

MACHINE

The unsafe
act
The unsafe
condition
The remedial
measure

MEDIA

Figure 4.6 : Multiple
intersecting causes

Climbing the defective
ladder
The defective ladder
Remove or repair the
defective ladder and
train that worker

As per the multiple causation
theory some of the contributing factors
surrounding this accident can be found
out by asking :

In this theory1. Man includes- workers, public etc.
2. Machine
includesequipment,
vehicle etc.
3. Media
includesenvironment,
weather, roadways etc.

16

1. Why was the defective ladder not
found in normal (past) inspections?
2. Why did the supervisor allow its use?
Why did he not get it repaired
urgently?
3. Didn’t the injured worker know he
shouldn’t use it?
4. Was he properly trained or not?
5. Was he reminded or cautioned?
6. Did and do the supervisor examine
the job first?
The answers to these and similar
questions would suggest the following
measures:
1. An improved inspection procedure.
2. Repairing the ladder (machine, tool,
job etc.) immediately i.e. not waiting
for an accident.
3. Improved training and supervision.
4. Better fixation of responsibilities.
5. Pre job planning and checking by
supervisors.
Thus application of the multiple
causation theory leads us to deep
causation
analysis
and
improved
management systems are suggested to
eradicate the problem from its origin.
The range and depths of the multiple
causation factors provide much details
of long-run safety measures.

Decisions

Risks

Accident

This necessitates the introduction
of feedback system (as shown in
diagram) to find out the faults/causes in
man, machinery and environment. The
information that the man possesses can
be strengthened through training. The
stressors can be precedent in the
following form -

7.5 Systems Model Theory:



Machine
Environmen
t






1. Psychologica
l stressors

-

2. Environment
al stressors

-

3. Physiological
stressors

-

Anxiety,
aggressiveness,
fatigue.
Glare, temperature
extremes and low
levels of illumination,
also includes
‘Machine stressors’
like unguarded
machines at the
point of operation,
transmission of
power and other
dangerous parts.
Narcotics & Alcohol.

7.6 Ferrell’s Human Factors
Theory:

Similar to V.L. Grose’s multiple
causation
theory,
Bob
Firenze
developed a system model theory as
under.
Here interaction between man,
machine and environment (basic preelements for any accident) leads to an
accident if the information available to
the important element of the system is
inadequate. If the risk is high and the
decisions based on information are
illogical and unsound, an accident
occurs resulting into incompletion of the
task. Bob Firenze’s system model is
shown below:
Man

Task

Dr. Russell Ferrell, Professor of
Human Factors at the University of
Arizona, gave this theory of accident
causation as shown in diagram below:

Overload
(load,
capacity,state)
Incompatibility
Improper
activities

Unsuccessful task
feedback
Stressors


17

 



Human
error

Initiating
incidents

Accidents

Outcome

s

(a) The worker did not know how to
do it.
(b) He deliberately took risk due to
-- low perceived probability of
accident
-- low perceived cost of
accident

Casual chain
This theory states that accidents
are the result of a casual chain (as in
multiple causation theory), one or more
of the causes being human error, which
is in turn caused by three situations overload, incompatibility and improper
activities. Factors affecting these three
situations are as follows :

Since this is basically human factor
model, greater emphasis is placed on
the first two causes of human error,
overload and incompatibility.

1. Overload (A mismatch of capacity,
load
and a state) due to (a) Load
Task (Physical, information
processing)
Environment (Light, noise,
distraction, stressors that
require active coping)
Internal (Worry, emotional
stress)
Situational (Ambiguity of
goals or criteria, danger)
(b) Capacit Natural endowment,
y
physical condition, state
of mind, training,
drugs, pollutants,
pressure, fatigue,
stressors that impair
ability to respond
(c) State
Motivational level and
arousal level

7.7 Petersen’s Accident
Incident
Causation
Theory:

This theory adapts Ferrell’s human
factors of overload and also Heinrich’s
domino theory and states that causes
of accident/incident are human error
and/or system failure. Human error is
due to overload, traps and decision to
err. Human error may directly cause
accident or may cause system failure
which may cause accident resulting in
injury or loss as shown below:
Overload

Traps
Decision
err

2. Incompatibility
(incorrect
response or mismatch) due to (a)

(b)
(c)

(d)
3.

Stimulus
Respons
e
Stimulus
Stimulus
Respons
e
Respons
e
Work
station

-

to

System failure

due to control - display







Human error

Accident or
incident

Injury
loss

or

Factors causing overload are much
the same in Ferrell’s model.
Traps
are
due
to
defective
workstation, design and incompatible
displays or control.
Decision to err are caused by
illogical
decision
under
situation,
unconscious desire to err and perceived
low probability.
System failure is due to policy,
responsibility, authority, accountability,
measurement, inspection, correction,
investigation,
orientation,
training,
selection, Safe Operating Procedure,
standards, hazard recognition, records,
medical and others.

due to inconsistent
display types
due to inconsistent
control types or
locations
size, force, reach, feel

Improper Activities due to -

18

questions will lead to inevitable injury.
An accident can be the result of many
different routes through the model (20
routes). There are fewer routes leading
to no-injury situations.

7.8 Epidemiological Theory:
Suchman stated epidemiological
definition
of
accident
as
“An
unexpected, unavoidable, unintentional
act resulting from the interaction of
host (accident victim), agent (injury
deliverer) and environmental factors
within situations which involve risk
taking and perception of danger”. His
model is shown below:
Predisposition
characteristics
-- Susceptible
host
-- Hazardous
environment
-- Injury
producing
agent



7.10 Energy (Release) Theory
:
Dr. Leslie Ball, former Director of
Safety for NASA, introduced a causation
theory. His thesis is that all accidents
are caused by hazard, and all hazards
involve
energy,
either
due
to
involvement with destructive energy
sources or due to a lack of critical
energy needs. This model is most useful
to identify hazards and to understand
system safety.
Gibson noted that injury to a living
organism can be only by some energy
interchange. Hence it was suggested
that the energy exchange should be
considered as the injury agent. The
energy exchange resulting in an injury
could
be
mechanical,
chemical,
thermal, electrical etc. This concept is
useful in understanding the way injury
is caused and examining the solutions.
When a grinding wheel is in stopposition it does not make accident, but
if it runs and fingers trapped, it makes
accident because of its kinetic energy.
William Hadden, in 1970, explained
‘energy transfer or release’ as the main
factor for accident causation and said
that accidents and injuries are caused
because of transfer or release of energy
between
objects,
events
or
environment interacting with people.
Based on this theory, Hadden
suggested ten strategies to prevent
or reduce losses as under:

Situational
characteristics
-- Risk taking
--

Appraisal of
margin error


Accident

conditions
-- Injury
-- Unexpected
-- Damage
-- Unavoidable
-- Unintentiona
l
This originated with the study of
epidemics. Casual association between
diseases or other biological processes
(accidents) and specific environment
are studied. A classic example of
epidemiological method was given by
Snow who discovered that persons
using a particular water supply had a
higher death rate from cholera than
others.
Gordon
and
McFarland
supported that accidental injuries could
be studied with the same techniques.
Accident effects

7.9 Surry’s Decision Theory:
Jean Surry developed this theory
stemming from the epidemiological
model of Suchman. It assumes that by
a person’s action or inaction danger
occurs to the person. If any negative
responses to the question are shown
during the danger build-up cycle, the
danger becomes imminent. If all replies
are positive, the danger diminishes and
a negative response to one of the

1. Prevent the transfer or origin of
energy. e.g. safe substitution - using
toluene instead of benzene, not
keeping the car running, dipping
instead of spraying, shot blasting
instead of sand blasting.
2. Reduce the amount of energy
transfer. i.e. drive vehicle or
machine at slow speed, reduce

19

quantity
or
concentration
of
hazardous chemicals.
3. Prevent release of energy. e.g.
flameproof
electric
fitting
in
flammable area, fall arrestor device,
dyke to stop spread of chemical,
safe overflow pipe or level cut off
device.
4. Change the rate of release or
distribution of released energy. e.g.
reduce the road slope, use inhibitor
to reduce rate of reaction, sprinkler
to reduce rate of burning, scrubber
to scrub toxic gas, condenser to
liquefy organic vapour.
5. Divert
(separate)
the
energy
released in time or space. e.g.
separate paths for vehicles and
pedestrian traffic, keep electric
wiring or pesticide out of reach,
discharge gases at height.
6. Provide barrier between the energy
released and a structure or a person
likely to be affected. e.g. guards on
machines, radiation shield, filter,
safety goggles, earplugs, insulation
on hot surface, blast wall against
explosion energy.
7. Make the surfaces of structure safe.
e.g. rounded corners, blunt objects,
big handles of tools and no sharp
edges.
8. Strengthen the structure or person
susceptible to damage. e.g. fire
resistant wall, training to workers
and vaccination for disease.
9. Early detection of damage and
actuate counter effect. e.g. fire
detectors with sprinklers, high level
alarm and tripping of feed pump,
temperature alarm and starting of
cooling system.
10. Speedy measures to restore normal
condition. e.g. rehabilitation of
injured worker, repairing of a
damaged machine or vehicle.
See Part 5 of Chapter-2 for safety
philosophy on accident causation.

understand
the
principles
and
techniques of accident prevention. But
before that we will see the types of
accidents first.

8 PRINCIPLES
OF
ACCIDENT PREVENTION

8.2
Fundamentals of
Accident Prevention:

After understanding the causation
of accidents, it is obviously essential to

As explained by Heinrich, accident
prevention is both, science and art. It

8.1

Types of Accidents:

Based
on
severity
of
injury,
accidents are major, minor or near miss
type. The combination of injury and
property damage gives four types of
accident as follows:
1. Injury and property damage (major).
2. Injury and not property damage
(major or minor).
3. Property damage and not injury
(major or minor).
4. No property damage and no injury
(near miss).
Based on causation, they are also
of four types:
1. Psychological causes - such as
inexperience, not motivated for
safety, worry, emotional, wrong
attitudes etc.
2. Physiological causes - such as
age, sex, body-build, hearing, vision,
strength etc.
3. Physical causes - such as heavy
workload, long working hours, no
rest, unhealthy work environment,
work at height, depth or in confined
space, falling load etc.
4. Mechanical,
Chemical
&
Environmental causes - such as
unguarded
machinery,
defective
equipment,
noise,
vibration,
obstructed pathway, sharp edge,
poison, toxic gas, acid, heat, cold,
humidity, fire, explosion, lightening
etc.
Causes of type No. 1 and 2 give rise
to unsafe action while No. 3 and 4 give
rise to unsafe conditions.

20

SAFETY
5

represents control of performance of
man,
machine
and
physical
environment.
The
word
‘control’
includes
prevention as well as correction of
unsafe
conditions
and
actions.
Prevention is an advance part of
‘control’ which if practiced, subsequent
control for consequence or effect may
not be needed. Thus accident control is
a vital factor in every industry, which if
ignored or practised unskilfully, leads to
needless human suffering and business
bankruptcy.
The
accident-prevention
task
requires both, the immediate approach
(direct control of personal performance
and environment) and the long-run
approach of instruction, training and
education. This task must be performed
before an accident and injury occur.
Subsequent efforts after accidents are
also necessary.
Thus accident prevention may be
defined as an integrated programme, a
series
of
co-ordinated
activities,
directed to the control of unsafe acts
and unsafe conditions and based on
knowledge, attitude and ability for
safety. It aims to serve industry,
country and humanity.
Five basic or fundamental steps for
accident prevention (safe and efficient
production),
suggested
by
H.W.
Heinrich,are :
1.
2.
3.
4.
5.

4
3
2

Application of remedy

Selection of remedy

Analysis

Fact finding

Fig. 4.7
Steps of Accident Prevention
Organisation
1

8.2.1 Organisation:
As shown in Fig. 4.7, organisation is the
first step of accident prevention work.
The
safety
organisation,
management or at least the planned
procedure, which it represents, is the
vehicle, the mechanism by means of
which interest is kept alive and the
safety programme is designed, directed
and controlled. The actual work of
prevention is done by safety director or
manager, safety officer and the line and
staff supervisors with the active support
of top management. See Chapter -7 on
safety management.
Safety is not only a staff function
but it is a line function also. Budgetary
provision (cost allocation) for safety
should be made from very beginning.
Here organisation does not mean
safety department only. Safety is not a
function of one department only. All the
members of organisation (including all
departments) have to contribute and
play their role for safety.
Basic philosophy and safety policy
for accident prevention and firm
determination of the top management
are utmost necessary.
Organisation also includes single
person working for safety.

Organisation.
Fact finding.
Analysis of the facts found.
Selection of remedy and
Application of the remedy.

8.2.2 Fact Finding :

Sixth step of ‘Monitoring’ (i.e.
measurement of result, assessment i.e.
comparison with legal criteria or
standard,
feedback
and
further
improvement) is also suggested.

The knowledge of probable or
potential hazards (facts) is derived from
surveys, inspections, safety audits,
observations, review or records, inquiry,
investigation and judgement.
The term “hazard” is synonymous
with the phrase “direct and proximate
accident cause” i.e. the unsafe personal
act and/or unsafe physical, mechanical
or chemical condition without which no
accident can occur.

21

Personal hazards (unsafe acts) are
violations of commonly accepted safe
practice/procedures.
Mechanical
hazards (unsafe conditions) are of four
groups : Static, kinetic, electrical and
chemical (including radioactive or
nuclear).
Heinrich classifies main causes of
accident as under:

Some reasons of unsafe acts are as
under:
1. Improper
Attitude
Wilful
disregard, reckless, lazy, disloyal,
non
co-operative,
fearful,
oversensitive,
egoist,
jealous,
impatient,
absent-minded,
excitable,
obsession,
phobia,
inconsiderate, intolerant, mentally
unsuited and other psychological
reasons.
2. Lack of knowledge or skill Insufficiently
informed,
misunderstands, not convinced of
need, indecision, inexperienced etc.
3. Physically Unsuited – Due to
hearing, sight, age, sex, height, ill,
allergic, slow reaction, crippled,
intoxication, physically handicapped
and other physiological reasons.
4. Physical conditions - Space, light,
ventilation,
heat,
layout
or
arrangement,
materials,
tools,
equipment, procedures, company
policy,
routing
etc.
make
it
awkward, difficult, inconvenient,
embarrassing or impossible to follow
safe-practice rules.

Accident
Preventable

Unpreventable

Cause (direct or contributory)
Unsafe act

Unsafe condition

Error
Ignorance
Deliberate
Underlying cause
human fault

Mechanical
Physical
Chemical
Environmental

The proximate cause is the nearest
in ‘efficiency’ rather than whether it
was closest in time or not.
13 unsafe acts and 13 unsafe
conditions are listed in foregoing Part
7.1 entitled ‘Heinrich’s theory of
accident causation’. These are some
general heads or categories under
which more specific acts may be
grouped. For example, the general head
“Making safety devices inoperative’ can
be sub-itemised as:
1. Removing guards.
2. Tampering with adjustment of guard.
3. Beating or cheating the guard.
4. Failing to report defects etc.
Two types of main facts – unsafe
acts and unsafe conditions - are
discussed below.

Unsafe act should be noticed as early
as possible and removed just after it is noticed.
Purpose should be of removing injury, to
prevent recurrence and not to punish any
individual.
Workers
should
be
properly
observed for their unsafe act by seeing
their selection and use of –
1. Position of
working.
2.

their

standing

and

Tools and equipment including hand
tools, power tools, lifting tools, PPE,
FFE etc.

3. Method or procedure adopted by
them.
4. Traffic and driving rules.
Position and working should not be
in dangerous conditions. Tools and
equipment should be of correct size and
type, should be used correctly and in
right condition. Procedure or method
should be safe and adequate. Where
safety work permit is required, it must
be explained and followed correctly.
Driving should be safe or defensive and

8.2.2.1 Unsafe Acts:
Unsafe act is a human action
resulting in accident or injury to him,
others, environment or all. See also part
3.94 of chapter – 2 for definition of
‘unsafe act’.

22

traffic rules must be observed. Drivers
of vehicles of hazardous goods should
have undergone specific training.
After
seeing
an
unsafe
act,
observer’s (e.g. supervisor or safety
officer) attitude should be to ‘talk with’
the worker and not to ‘talk to’ the
worker. This means to call or advise the
worker
politely, ask him why he is
doing so or not using required tool,

equipment, procedure etc., hear his
explanation, try to understand him and
then explain him the ‘underlying
hazard’ and make him convinced about
‘unsafe act’ and to correct it as per
safety requirement.
Some examples of unsafe acts and
control measures are given in Table
4.1:

Table 4.1: Unsafe Acts, Remedies and Responsibilities
Unsafe Actions or
Behaviouristic Causes
1 Age, sex, experience

Remedies

2 Physical and
physiological conditions
such as
work-load, physical
strain, physical
weakness,
headache, cold,
faintness, abnormal
blood pressure,
poor vision,
handicapped, deaf,
dumb, epilepsy etc.
3 Poor attitude and
inability such as
inattentive,
insubordinate,
un-cooperative, critical
of supervision, bad skill
or motives, wrong
habits, intoxication,
chance
taking, absent minded,
disregard of safety
rules & instruction etc.

A

4 Human errors such as
intentionally performed,
due to - behaviour
components, personal
factors, situational
factors, and lack of
knowledge, training etc.

Personnel Dept.
A

Supervisor, Safety
Officer

B

Pre-employment
medical exam.

B

Physician, Factory
Medical Officer

C

Periodic medical
exam.

C

Physician, Factory
Medical Officer

D

Proper placement of
person

D

Physician and
Personnel Dept.

A

Pre-employment
psychological or
ability tests

A

Psychologist and
Personnel Dept.

B

Supervision

B

Supervisor

C

Discipline

C

Supervisor and
Personnel Dept.

D

Personnel work

D

Personnel Dept.

A

Mechanical, physical,
chemical safeguards
and safety rules
Safety education,
training, meeting,
contest, posters,
maintaining, interest
and awareness
Job analysis and
revision
Pre-employment tests

A

Safety & other
Engineers

B

Supervisor and Safety
Training Dept.

C

Production & Safety
Manager
Psychologist and

B

C
5 Emotional factors such

Proper selection of
personnel
Workload study and
proper distribution

Responsibilities

A

23

A

as worry, hurry, fatigue,
accident proneness &
tendencies, home or
social difficulties, loss of
sleep, periodical
emotional disturbances
etc.

B

Supervision

B

C

Maintaining interest
and awarness
Critical incident
technique

C

D

D

Personnel Dept.
Supervisor
Supervisor and Safety
Officer
Expert

Such unsafe conditions are due to
non-provision, non-maintenance, poormaintenance, poor-supervision, lack of
training, improper design and layout of
plant & machinery, absence of guards
and safety devices, failure of safety
devices, equipment or tools, unsafe
structure, poor housekeeping, fire-prone
area, sources of ignition, static electricity,
slippery floor, high noise, vibration,
lighting, radiation, poor ventilation etc.

8.2.2.2 Unsafe Conditions:
See Part 3.95 of Chapter – 2 for
definition of ‘unsafe condition’.
Unsafe condition is created by an
unsafe act of a person or act of God or by
any agency or due to failure or weakening
of any material, structure, situation,
condition or system.
Observance of unsafe conditions
includes many areas such as
proper
lighting, ventilation, housekeeping, floors,
platforms, handrails, toe guards, machine
guards, tanks, vessels and pipelines,
safety fittings and devices, electrical
hazards, fire prone condition, gaseous
and dust exposures, noise, vibration,
atomic radiation, loading, unloading and
transportation etc.

Observation
for unsafe
working
conditions
should
include
basic
techniques of look, listen, smell and feel
(LLSF) to detect unusual condition of
situation, position, noise vibration, odour,
temperature, pressure, out of control etc.
Some examples of unsafe conditions
and control measures are given in Table
4.2:

Table 4.2: Unsafe Conditions, Remedies and Responsibilities
Unsafe Conditions or
Environmental Causes
1
Atmospheric conditions
such as contents of air,
temperature, humidity,
ventilation, rain,
lightening etc.

2

3

Illumination, its
distribution and diffusion
- direct glare, reflected
glare, shadow and
colour
Workspace,
overcrowding,
obstructions etc.

Remedies
A
B
C

A
B
C
A
B

Responsibilities

Air sampling,
monitoring, cleaning
and conditioning.
Humidity control.
Improve natural and
artificial ventilation
by efficient exhaust
systems.
Improve natural and
artificial illumination.
Good design and
plant layout.

A

Engineering and Utility
Dept.

B
C

Humidity Dept.
Engineering Dept.

A

Lighting Dept.

B

Plant Engineer

Proper colour.
Proper spacing, area,
height, machinery
layout, headroom.
Good design and

C
A

Colour expert
Plant Engineer, Civil
Engineer

B

Plant Engineer,

24

4

Bad housekeeping,
rubbish, disorder,
unplanned layout

A

5

Inherent properties and
design defects of
materials, machines,
equipment, buildings
etc.

A

6

Improper guarding like
no-guard, inadequate
guard, no maintenance
etc.

A
B

8

Design Engineer, Plant
Engineer, Safety
Officer, Purchase Dept.

A

C

Supervisor, Safety
Officer
Chief Engineer,
Purchase Engineer,
Safety Officer
Supervisors

A
B

Supervisors
Maintenance Dept.

C

Purchase Dept.

A

Production or Plant
Manager, Safety Officer
Training Officer,
Supervisors
Safety Officer

Unsafe methods,
procedures etc.

A
B

Job training.

B

C

Safety rules &
procedures.
Inspection and
correction.
Proper speed of work.
Time study, Motion
study, job study,
machine study etc.
Noise measurement
& controls.
Use of ear plugs, ear
muffs etc.
Vibration detection &
controls.
Supervision.

C

Regulation of Law.
Provide sufficient &
good facilities of
toilet, urinals,
washroom, lunch
room, canteen etc.
Provide safe clothing
& PPE.
Detection of hazards
by various

B
A

Personnel Dept
Personnel Dept, Chief
Executive

B

Personnel Dept.,
Supervisors
Supervisors, Safety
Dept. Technical Dept.

C

Rate of Production

A
B

1
0

Noise & Vibration

A
B
C

Long working hours or

A

excessive workload
Insufficient or improper
welfare facilities,
clothing, PPE etc.

B
A

B
1
3

A

A
B

9

1
2

Supervisor
Plant Engineer, Safety
Officer

Defective materials,
tools, equipment,
vessels, stairs, pits,
tanks, objects
etc.

D

1
1

A

Include guards in
original design, order
& contract.
Provide and maintain
guards for existing
hazards.
Regular inspection.
Preventive and
corrective
maintenance.
Good source of
supply.
Job safety analysis.

C
7

housekeeping.
Good housekeeping,
orderliness,
cleanliness, planned
layout.
Good design, good
materials, good
construction &
maintenance, good
procedures
conforming to
standards.
Regular inspection.

Hazards in chemical
industries, processes,

A

25

B

D
A
B

Supervisor,
Safety Officer
Production Manager
Supervisor, Safety
Officer

A

Plant Engineer

B

Supervisors, Safety
Officer
Plant Engineer,
Supervisors
Supervisors

C
A

A

1
4

1
5

storage, transportation
etc.

B

Emergencies & Disaster

A

Act of God and
unexpected events

techniques.
Application of
appropriate remedy
such as safe guards &
fittings, safety
devices, elimination
of hazard,
minimisation of
hazard level,
lockouts, trips &
interlocks, isolation,
fail-safe design,
failure minimisation,
failure rate reduction,
screening, scrubbing,
monitoring i.e.
sensing, measuring,
responding, and
warning (audiovisual) of dangerous
parameters, remote
controls,
microprocessors,
recorders, auto
controllers etc.
Onsite
Emergency
Plan.

B

Chief Engineer.
Plant Engineer.
Production Engineer.
Chemical Engineer.
Supervisors,
Safety Officers.

A

Chief Executive, Safety
Officer, Fire Officer,
Emergency Staff
Govt. authorities,
mutual aid,
associations etc.
Design Engineer.,
Top Management
Chief Executive, Safety
Officer, Fire Officer,
Emergency Staff

B

Offsite
Plan.

Emergency

B

A

Assessment and safe
planning.
Onsite
Emergency
Plan.

A

B

Facts from Accident Reports:

B

The third step to accident prevention
is analysis of the facts found. This is
defined
as
the
work of drawing
conclusions from assembled data. The
hazards are here named, identified and
analysed. Such work is done by (a)
Analysis of past experience (b) Survey
and inspection (c) Judgement and
experience plus enquiry. Identify the
direct causes, sub-causes, underlying
major
causes,
types
of
accident,
operations,
tools
and
equipment,
obstacles, frequency, severity, location,
occupation etc., and classify them.
The supervisor’s report of accident
investigation is the basis of all analysis of
past and present accidents. It is the most
important, difficult and skilful task
requiring
good
knowledge
and

Form No. 21, 21A and 29, under the
Gujarat Factories Rules and Annex –13
under the Electricity Rules prescribe some
facts for accident reporting which should
be referred for information.
Facts should include ‘past facts’ of
accidents already happened and ‘future
facts’ of possible accidents based on
various hazard identification techniques
such as Hazop, Hazan, Safety audit, risk
assessment, FTA, ETA, etc as stated in
Part 1 of Chapter - 19.

8.2.3 Analysis of the Facts :

26

experience. Decide very carefully that
which is the unsafe act, which is the
unsafe condition, which is more proximate
and the accident is due to any one or
their combination and in which sequence.
From facts, witnesses and rational
judgement find reply to all these
questions and report properly for real
accident reporting and true causation
study.
Twelve
steps
(safety
officer’s
procedure) to analyse the causes of
accidents are as follows :

the named (analysed) hazards. Four basic
remedies are as under :

Four Basic Remedies:
1. Engineering Controls : Guarding of
machine and tools, isolation of
hazards, revision of procedures and
processes,
good
illumination,
ventilation, colour and colour contrast,
substitution of safer materials and
tools, replacement, reduction, repair
and a variety of mechanical, physical
and chemical remedial measures for
which the most of the chapters of this
book are developed.
2. Instruction, Training, Persuasion
and Appeal: Regular training as well
as
instruction,
re-instruction,
persuasion, appeal, notice, posters,
supervision and motivation.
3. Personnel adjustment: Selection
and placement with regard to the
requirement of the job and the
physical and mental suitability of the
worker,
medical
examination,
treatment, advice and PPE.
4. Discipline:
Mild
admonition,
expression of disappointment, fair
insistence, statement of past record,
transfer to other work and penalties.

1. Obtain the supervisor’s report of the
accident containing the details given
above.
2. Obtain statutory accident report form.
3. Obtain the injured person’s report.
4. Obtain the reports of witnesses if any.
5. Obtain the doctor’s report on injury.
6. Investigate the accident.
7. Record all evidences and facts.
8. Tabulate the essential facts of the
given accident together with the
similar past accidents.
9. Study all the facts.
10. Analyse accident causes in details.
Such analysis will classify causes as
defective or no guard, poor lighting,
poor ventilation, no safety devices, no
use of PPE, accidents – fatal or
nonfatal, male or female wise, day or
night wise, age wise etc.
11. Arrange the causes in order of
importance or priority of compliance.
12. Find and record reasons of existence
of those causes.

In the process of selecting an
effective remedy, ‘Engineering Control’
takes the first place and discipline as the
last resort. Select the most effective and
urgent remedy first and then precede
priority wise.

After finding potential hazards, cross
analysis of records must be made to
select most important hazards or targets.
Reasons for existence of hazards must be
found for correction.
Appraisal, analysis, inspection and
control
techniques
are
separately
discussed in details in Chapter-19.

8.2.5 Application of the Remedy:
The final step in accident prevention
is application of the selected remedy.
If
machines,
tools,
vessels,
equipment, structures, procedures etc.,
are unsafe, they must be guarded,
replaced, revised or otherwise made
mechanically safe or accident free. This is
management’s responsibility. The safety
officer/engineer will guide and the
supervisors see to it that the necessary
work is done.
If the personal performance is unsafe,
employees must be selected, instructed,

8.2.4 Selection of Remedy:
When it is analysed to indicate which
is the proximate or main cause that
needs to be corrected then it suggests
the fourth step of selection of remedy for

27

trained, cautioned, persuaded, convinced
and appealed for improvement. Certain
cases require proper placement, other
medical or psychological treatment or
advice. In rare cases and as a last resort,
some form of disciplinary action may be
needed.
Application
of
selected
safety
measures should be immediate and longterm. Existing unsafe conditions and
actions should be corrected at once while
at the same time long-term programmes
should be started to include procedures
and techniques devised to anticipate and
prevent situations of a similar nature.
Application of remedy is the dynamic
part of accident prevention. Unless the
remedy is successfully applied, all prior
steps are of no use and wasted.

carry out all such functions singlehandedly. All employees are expected to
work safely. Responsibility should be fixed
and distributed for quick compliance. A
supervisor or foreman is the key-man for
such purpose.
Machine - accidents are controlled by
effective engineering-revision. But many
accidents take place in material handling
for which two highly successful methods
may be employed. One lies in the study
and improvement of methods and
procedures to the end that some safer
and better way or equipment may be
found to conduct any particular operation
than that in use. Secondly, it is most
useful to utilise the proper degree of
supervision - from the chief executives
down to the foreman - that will result in
the observance and correction of unsafe
material handling practices on the part of
the workers before injuries occur.

8.2.5.1 Ways & Means of Application
of
Remedy : A safety engineer or
officer applies the following ways :
1. Prepares,
presents
and
applies
recommendations,
suggestions,
summaries and plans.
2. Establishes a safety organisation.
3. Gets support of management and
supervisory staff in applying the
remedies.
4. Creates enthusiasm and co-operation
up and down the line.
5. Satisfies himself by seeing the
successful working of the remedies
applied.

8.2.5.2 Creating and Maintaining
Interest:
The
second
basic
remedy
of
persuasion,
appeal,
instruction
and
training requires vast efforts. The practice
of creating and maintaining interest for
accident prevention applies to employers
as well as employees.
Group interest of employees is
created and maintained by the safety
organisation which includes moral and
educational
effect
of
accident
investigation, publicity, posting and
distribution of educational literature,
safety films and slides, contests, prizes,
awards, meetings and inspirational talks.

He will apply in chronological order
the four basic remedies mentioned in the
foregoing Part 8.2.4. Engineering controls
call for designing, buying and building,
installing and maintaining guards, safety
devices and safety equipment. The
persuasion and appeal remedy requires
teaching, training, appeal, instruction,
persuasion etc.
He must have ability to overcome
obstacles in applying remedies. He should
identify the obstacles as a person,
attitude, condition or circumstance.
Constant follow-up action through
safety
administration
is
necessary.
Detection and placement of physically
impaired workers should be carried out
carefully and effectively. In a typical oneman plant the employer himself has to

See part 8.7 to 8.9 of Chapter -3 and Part
8.2.4 of Chapter -6.

Individual interest of employees is
created and maintained by an appeal to
personal characteristics listed below:
1. Self-preservation (Fear of personal
injury)
Featuring the injury by figures, posters,
notices, meetings, oral discussion,
lectures, films and slides are useful to
maintain
the
strongest
and
commonest human instinct of selfpreservation or self-protection.
2. Personal and material gain (Desire
for reward)

28

3.

4.

5.

6.

7.

8.

9.

Bonus, salary increase, vacation with
pay, days off, trips, personal gifts,
requisite
assignments
of
work,
banquets, picnics and participation in
safety activities prove useful in this
regard.
Loyalty (Desire to co-operate)
Effect of accident by the employees on
supervisor’s record, on employer’s
overhead cost, on quality of product,
on
fellow
employees
and
on
company’s prestige must be brought
to the notice of individual to create
and maintain their sense of loyalty to
the employer.
Responsibility
(Recognition
of
obligation)
The sense of responsibility, both to self
and
to
others,
is
created
by
assignments
and
analogy
of
observance of safety rules.
Pride (Self satisfaction and desire for
price)
Pride increases ability to work. Praise
exhibits,
awards
and
insignia,
differentiation
of
workers
having
outstanding safety record by giving
them special hat/dress, reward etc.,
are useful in this regard.
Conformity (Fear of being thought
different from others)
Some
methods
of
appeal
are:
Standards (Safe practice rules, codes,
procedures etc.), comparison, system
and regularity, leadership of good
example in safe conduct, ridicule, etc.
Rivalry (Desire to compete)
Man is a highly competitive animal and
creates better results when competing
with other than when working alone.
For this, provide opportunity, set up
objectives and determine method of
measurement.
Leadership (Desire to be outstanding)
The desire for leadership is strong in
many persons which may be used to
advantage in safety work. Such
persons should be given additional
responsibility in safety work and
promotion etc.
Logic (Special ability to reason)
Some persons have special ability to
see both sides of a question and to
arrive at conclusions that are logical
and just. Such persons should be used

in safety work. A few methods of
appeal to logic are basic philosophy of
accident causation and prevention and
providing data relating to accident
frequency and severity, accident types
and causes and remedial measures.
10. Humanity (Desire to serve others)
Humanitarianism is a widely spread
human instinct and strong appeal to
everybody for safe performance.
Safety
is
termed
as
Human
Engineering on this ground where
human is expected to be at centre. We
have to fit the unfit to survive.
8.2.5.3 Education:
All
accident-prevention
work
is
basically educational. Well-trained and
careful men may avoid injury on
dangerous work and untrained and
careless men may be injured under the
safest possible conditions.
Safety education is meant to include
meetings and talks, personal contacts
with authorities or teachers, use of
bulletins, posters, lectures and reading
material, slides and films, computers,
first-aid instruction and any oral or written
instruction for avoiding hazards and
cultivating safe methods of doing work.
Some of the most commonly used
educational procedures are listed below:
1. Regular safety coaching class for
workers. Hazards, safety precautions,
safety measures, safety duties and
procedures should be explained in
their own language.
2. Periodical safety class for supervisors,
managers and top executives for coordinated efforts from all.
3. Safety meeting, conference, seminar,
exhibition etc.
4. Publicity-Safety
posters,
slogans,
maxims,
notices,
bulletins,
paypocket-inserts, stickers, slides, films,
house magazine etc.
5. Safety books, pamphlets, periodicals
etc.
6. Safety contests, essays etc.
7. Safety plays and similar programmes.
8. Preparation of safety codes, standards
etc.
9. Use of loyal employees in setting a
good example.

29

10. Safety message on work orders,
computers, correspondence etc.
11. Featuring specific safe-practice rules.
12. Investigation
of
accidents
and
explaining their analysis of unsafe
actions, unsafe conditions and their
remedial measures.
13. Conducting training programmes.
14. Sending persons to outside safety
courses.
15. Specific programmes as per our own
need and nature of work.
16. Conducting short-term safety course
for all employees in rotation.

8.3
Models
Prevention:

for

Errors

Error Rate
Reduction
Measure

This model is discussed by Johnson in
MORT (management oversight risk tree).
Here errors are considered inevitable,
situtations error-provocative, rate of error
measurable and reducible. Situation can
be changed by study, practice and
participation.

8.3.3 Performance Cycle Model :
Decision

Accident
Analysis

H.W. Heinrich’s model of ‘Five steps
of accident prevention’ is explained in
previous Part 8.2 and shown in Fig. 4.7.
The other relevant models given in
Heinrich’s book (ref. no. 1) are explained
below in brief.

Problem
Feedback or
Measureme
nt

8.3.1 Kepner-Tregoe Model :
Measure

Problems

Execute

Johnson has discussed this model in his
MORT. Here five steps in sequence are
problem, its analysis, decision, action and
measurement of result. It may be again
analysed for re-decision.

Problem
Analysis

Potential
Problem
Analysis

Decision
Analysis

8.3.4Updated
Management Model:

Choose

Collect Data

Human
(Error

Philosophy,
Practice,
Study

Safety

Fundamental approach to
accident prevention
(safety management)

This model is very close to Heinrich’s
five step model shown in Fig. 4.7.
‘Execute’ means application of remedy.
‘Measure’ is a new step in this model,
requiring measurement and monitoring of
the execution.

8.3.2 Improving
Performance
Reduction) Model:

Action

Monitor

Analyse
Data

Apply
Remedy

Select
Remedy

Assistance
Situation
Change

Long term Safety
Programs

Participation

30

Short term
Safety
Considerations

difficult job (d) Job safety analysis and (e)
Safety instructions for variety of jobs.

This is updated model of Heinrich’s five
steps model shown in Fig. 4.7. Here only
one step of ‘monitor’ is added for
monitoring of applied remedy and to
reconsider the problem.
Basic
philosophy
of
accident
prevention is required at the root of any
safety management. Monitoring is a
feedback mechanism, it tells us how we
are doing, what progress we are making.
It dictates additional needs, we then
collect additional data, analyse it, select
additional remedies, apply them, monitor
and so on.

8.4
Five ‘E’s
Prevention

of

3.

Enforcement (of safety rules)

All statutory safety provisions should
be followed for our own safety and safety
of others. Self initiation for full compliance
is necessary, otherwise government
authorities may take action. In addition,
other safety rules for our plant should
also be framed and followed. Wilful
neglect or disobey of safety rules or
orders should be dealt with strictly.
Enforcement measures include – new
law, amendment in old law, company
safety rules, implementation and legal
action.

Accident

4.

Safety or accident prevention can be
achieved by the following five methods:

Enthusiasm (to maintain interest)

Like a catalyst it adds to safety
awareness and motivation. It should
come from the top management to the
lowest worker. It will keep the workers
safety conscious. It can be developed and
maintained by proper safety competition,
prizes, awards, publicity, incentives etc.

1.

Engineering controls
(to prevent unsafe conditions)
Poor illumination and ventilation,
unguarded
machinery,
mechanical,
electrical, physical and chemical hazards,
dangerous location or situation etc., are
unsafe
conditions
which
can
be
eliminated in the design stage or
subsequent engineering revision and
controls. This is the first and most
effective remedy.

This
includes
motivation
participation in safety programmes.
5.

and

Example (to lead for safety)

The top executives, managers and
supervisors should set an example to
others by the self-enforcement of safety
rules. Then others will follow them. This is
a chain reaction to increase and maintain
safety.

Some engineering controls are–
substitution of less hazardous material,
risk
reduction,
process
modification
isolation, segregation, guarding, fencing,
barricading, enclosure, dilution, safe
design, failsafe device and safety devices
including alarms, trips, safety valve, NRV,
PRV, EFV, FFE, etc.

8.5. Approaches to Preventive
Action:

2.

Education & Training
(To prevent unsafe acts)
This has long-term and permanent
effect. This is the most powerful remedy
for unsafe act of the workers. It helps in
finding out unsafe conditions also. The
workers’ safety training programmes
should include (a) Understanding of
specific hazards of their plant, process,
building etc. (b) Safety rules and safe
procedures (c) Training for specialised or

Mainly there
approaches.

are

two

types

of

(1) Reactive
or
Corrective
Approach
(Effort after accident)
Accident

31

accident. This works as a lesson from the
accident.

↓
Investigation
↓

(2) Proactive
or
Preventive
Approach
(Effort before accident)

Analysis/
Assessment
↓

Identification of Hazards
↓

Preventive Action

Analysis /Assessment of Hazards
↓

Normal habit of a person or
management is to follow this reactive or
corrective
approach
only
after
an
accident. They do not think to invest
money or time for preventive measures
to avoid accidents by advance planning.
Drawback of this approach is to suffer
some loss due to one or more accidents.
In this approach, action is started after
accident.
Accident
causes
are
investigated analysed and preventive
action is determined. Then it is applied to
prevent
recurrence
of
the
similar

Preventive Programme
↓
Accident Prevention
In proactive or preventive approach,
action is to be started without waiting for
accident. Potential hazards are first
identified,
analysed
and
preventive
programme is formulated to remove or
reduce the hazards identified. This
approach is better then the reactive
approach, but it incurs regular costs.

EXERCISE
1.

Comment on the following
statements by giving your
opinion:

10. 88% accidents occur due to
‘unsafe acts’ of the workers.
Therefore there is no meaning in
wasting
money
to
improve
‘unsafe conditions’.
11. Accident happens due to multiple
causes, not by any single cause.
12. ‘Energy transfer’ is the main
cause of accident.
13. ‘Organisation’ is the first step of
accident prevention.
14. In accident prevention work,
search of ‘past facts’ (accident
record)
and
‘future
facts’
(possible accidents) both are
important.
15. ‘Engineering control’ is the best
remedy.
16. Without
application
of
the
remedy,
other
efforts
are
helpless.
17. All accident prevention work is
basically educational.
18. Reactive approach is preferable to
proactive approach.

1. Accidents are accidents. They just
happen. They cannot be caused
2. We prevent accidents because it
is our legal duty.
3. Productivity is more important
than safety.
4. Safety obstructs productivity OR
Safety retards production.
5. Safety and productivity are two
sides of a coin.
6. Legally ‘accident’ is not possible
without injury.
7. ‘Accident’ is also possible without
injury or damage.
8. Prevention of ‘near-miss’ is more
important
than
to
prevent
‘accident’.
9. Heinrich’s
ratio
theory
is
meaningless. Accident does not
give any warning or opportunity
to prevent it.

32

19. Supervisor should ‘talk to’ the
worker and not ‘talk with’ the
worker to explain his unsafe act.
20. Feedback or measurement of
result is useful in ‘performance
cycle model’ to correct our
preventive action.
2.

14. Criticism of Heinrich’s theory.
15. Facts
finding
for
accident
prevention.
16. ‘Unsafe
acts’
OR
‘unsafe
conditions’.
17. Four basic remedies for accident
prevention.
18. Ways and means to apply remedy
to prevent accidents.
19. Updated
Safety
Management
Model.
20. Two approaches to safety.

Write short notes or explain in
brief:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.

The accident problem.
Need for safety.
Reasons for accident prevention.
Factors impeding safety.
Meanings of ‘Accident’.
Types of ‘Accident’.
Types of ‘Injury’
Types of ‘Dangerous occurrences’.
Types of ‘Dangerous operations’.
Types of ‘Hazardous process’.
Notifiable diseases.
Ten Axioms of industrial safety.
Accident sequence.

3.

Discuss with details:
1. H.W.
Heinrich’s
Theory
OR
Frank Bird’s Domino Theory.
2. Multiple Causation Theory OR
William Hadden’s Energy Theory.
3. Five Fundamentals of Accident
Prevention.
4. Five ‘E’s of Accident Prevention.

Reference and Recommended Readings
1. Industrial Accident Prevention, H. W.
Heinrich, McGraw-Hill.
2. Safety and Health for Engineers, Roger
L. Brauer, Van Nostrand Reinhold, New
York.

3. The Factories Act 1948 and the Gujarat
Factories Rules 1963 with subsequent
Amendments.
4. The Workmen’s Compensation Act
1923 and Rules 1924.

33