In this article we will discuss about the nature of fatigue and accidents in industries. 


Fatigue describes a sort of “negative appetite for activity”. Fatigue means a reduced capacity for further work as a consequence of previous activity where a person was trying almost as hard as he could. Thus it includes both mental and physical reactions as well as the phenomenon of boredom and monotony.

Distinction is drawn in monotony, boredom, and fatigue. Monotony is a state of mind caused by performing repetitive tasks implying no emotional dislike. Boredom, or lack of interest, is characterized by depression and a desire for a change of activity. It is tinged with emotional distastes and is accompanied by a corresponding attitudinal outlook.

Thus, factors such as personality, attitude, and interest patterns affect boredom more heavily than monotony. Fatigue is a desire for a change in activity rather than for a rest or relief from work altogether. Feeling of tiredness, not necessarily accompanied by reduced the capacity to work.


The fatigue has three aspects:

i. Decline in quantity of work for a given level of effort;

ii. Feeling of tiredness, not necessarily accompanied by reduced capacity to work.

iii. Physiological change.


The most important physiological change is the accumulation of lactic acid in the blood caused by the breaking down of glycogen, or sugar, in the blood. Other physiological changes include junction of the nerve and muscle cell, change in the capacity of the nerve fiber to conduct, and possibly changes in the brain.

The physiological changes do not necessarily accompany changes in the production or in the feelings. Neither the physical changes nor feeling changes are as convenient to measure as the changes in production.

Studying the “feelings” of the fatigued person can also approach the problem of fatigue. When a man says he is tired out, is he describing the localized changes that have taken place in his body? Under conditions of strong motivation, men may continue work for long duration without being aware of fatigue, whereas, under other conditions, they may feel fatigued before they being to work.

In activity such as reading, a poorly motivated person will show various signs of fatigue after a relatively short period of time. However, when motivation is present, the same person will show no decrement in reading ability even after six hours of continuous reading.


It is believed that an individual’s attitude is an important factor in the ability to do work, but it is difficult to measure the presence or absence of attitude. Attitudes influence productivity and tend to cover up the expected effects in experimental studies dealing with the influences of rest periods on work. Any study of fatigue must control not only the actual physical activity, but also the indefinite environmental factors that influence a man’s outlook and attitude toward the work.

It is now become quite clear that emotional stability and mental hygiene cannot be divorced from fatigue, since emotional conflicts and attitudes are so closely related to fatigue that the latter cannot be defined without involving the other factors.

To the extent that fatigue involves the organism as a whole, it is a psychological problem. To the extent that work produces chemical and physiological changes in muscles, nerve tissue, and the blood, the problem is the concern of both biological chemists and physiologists.

Environmental Conditions Affecting Fatigue:

Various environmental conditions such as noise, improper light, and excessive heat tend to increase fatigue. In recent year vast changes have taken place in all these areas.


Many studies have shown that increased production, higher morale, and lower accident rate and les absenteeism tend to reduce fatigue:

(i) Noise:

Noise may cause sensory-motor, neuro-vegetative and metabolic disorders; it has been named as a cause of industrial fatigue, irritation, reduced productivity and occupational accidents. Prolonged exposure to noise above certain levels causes permanent damage to. Hearing and results in occupational deafness. Noise, or undesired noise, increases fatigue.

It is believed that production increases under conditions of quiet. One study of the reduction of noise found that under normal conditions reduction of noise will increase productivity by 10 to 15 per cent. The effect of noise depends on the kind of noise and the kind of work. Noise affects mental work more than manual work. The effect of noise is greater when it is irregular and interesting.


Loudness being the same, noises that have a higher pitch is more annoying than those of lower pitch. Sounds of either- very high or very low tone qualities are more irritating than those in the middle zone. Thus a person may tolerate the sound of certain intensity provided it falls into his middle zone of hearing, whereas he may be annoyed by a sound of equal intensity that has a high pitch or a very high or very low tone quality. Interrupted noise is generally more annoying than steady ones.

Noise requires more energy in order maintain performance at the same level. But this effect varies as people become used to the noise. Noise also causes muscle tension. The effect of noise on hearing is more than it is on fatigue.

That is why persons in occupations exposed to loud noise for a long time, such as boilermakers and airplane pilots, often suffer permanent deafness. Nobody should be exposed to levels of over 115 dB without hearing protection. Therefore, there is a need to control noise in industry.

(ii) Lighting:


Good visibility of the equipment, the product and the data involved in the work process is an essential factor in acceleration production, reducing the number of defective products, reducing waste and preventing visual fatigue and headaches amongst the workers. Both inadequate visibility and glare are frequently a cause of accidents.

Proper light requires right amount and kind for the job, an even distribution of light, and a minimum of glare. Units of the foot-candle is used to measure bright of light that is the amount of light that can just be seen from a source one foot away. The entire work area should be uniformly illuminated.

Areas outside the immediate focus of observation, if unevenly illuminated cause continual adjustment changes and consequently higher visual fatigue. Since the pupil of the eye must adjust itself when focusing on a bright spot and then on a dark spot, expansion and contraction of the pupil sets up an increased strain and fatigue in the worker.

Lighting should be adapted to the type of work. The level of illumination should be increased not only in relation to the degree of precision or miniaturization of the work but also in relation to the worker’s age


Indirect lighting is the best method of producing uniformity. Eye muscles tend to pull toward areas of high illumination. Where the high point of light is not in the work area, a tug-of-war exists between the muscles that are concentrated on the work area and those than veer to the higher illumination.

The human eye adjusts so readily to changes in illumination that the effects of poor lighting are usually not immediately observable to the untrained eye. Poor illumination causes fatigue and irritability, and a source of error and industrial accidents. Money spent to correct improper lighting will repay in terms of higher output per worker, lower production costs, and a generally happier, healthier, and a safer work force.

(iii) Color:

Lighting relates to the color of surrounding objects and surfaces. The careful choice of interior color schemes makes a valuable contribution to good lighting. The colors used at the workplace have psychological effects. It is better to select pleasuring rather than drab colors; the workers will see in this a clear sign that the management is making an effort to make working conditions more pleasant.

The use of white and light pastels improves illumination by reflecting a high percentage of light, while deeper tones have a considerably lower reflective value. There should be every effort to avoid glare. Studies show that people prefer the light of daylight color that assists materially in visual efficiency.

(iv) Heat:


Temperature level commonly faced in temperate zone working environments can affect worker productivity, comfort, and health. The effect of temperature on productivity becomes more pronounced as the physical effort required to perform the job increases, and it is highly dependent on the degree of humidity accompanying the temperature level. Degree of humidity affects both the speed of work and the length of voluntary rest pauses of workers. Low temperatures can also affect productivity.

However, individual differences make it difficult to set exact temperature and humidity limits within which all workers will be satisfied. The installation of air-conditioning equipment might well be a practical investment and not a luxury item. Where more severe conditions of temperature and humidity are encountered under industrial conditions, several things may be done.

Adequate ventilation, insulation, protective clothing and techniques of operation, which remove the worker from the source of heat or cold- all, are helpful. Rest pauses at frequent intervals under normal conditions of temperature and humidity and of sufficient length to permit full recovery will help.

How to Reduce Fatigue?:

The proper application of scheduled hours and rest pauses can go a long way in reducing the incidence of fatigue. Excessively long work- day’s increase only fatigue but also susceptibility to sickness, accidents and absenteeism. Reducing hours of work, hourly schedules, the distribution of rest pauses as to length, time and frequency yield higher hourly production. Most of these procedures raise efficiency because of their effect on monotony, motivation, and attitudes as well as fatigue.

(i) Hours of Work:

The effect of hours of work on output is not easy to identify because of changes in motivation that may be due to possible changes in pay. Output in relation to hours of work has been studies with respect to the length of the work- week and the workday, and also in terms of the number of days worked per week. Results may vary depending upon whether the work is heavy and whether done by men or women. In general, the highest productivity per hour has been noticed with a short work- week and with the working determining the pace.


(ii) Work Week:

What should be the length of the work- week? People are not unanimous. A study attempted to relate total production and output per hour to work weeks of 36, 40, 44 and, and 48 hours. The study exhibited although the 48-hour week turned the largest weekly output, it resulted in the lowest hourly output.

The 40-hour week, on the other hand, showed the highest hourly output, though not the greatest total weekly production. The 36-hour week gave less output per hour than the 40- and 44 hour weeks, but higher hourly production than the 48-hour week. According to this study, the optimum work week is the 40-hour week. As a general rule, the best records of output were found in plants that used wage incentives.

(iv) Workday:

The earliest study of the relation between hours of workday and production is one made by Robert Owen in 1816. He found that in his cotton mills as much work was done in a 10.5 hour day as in a 16-hour day. During the depression of the 1930s one plant changed from three 8-hour shifts to four 6-hour shifts 6 days a week.

In spite of two increases in pay of 12.5 per cent, the six-hour shifts were more economical to management because of increased production. In another study of the effect of hours per day on production, it was found that during a 5-day work week output dropped 4 per cent per hour when the workday was lengthened from 8 to 10 hours.


(v) Absenteeism:

Studies have found that lengthy hours of work and resulting fatigue have been responsible to increase absenteeism. A worker might desire to shop or may be making so much money he does not need to say on the job full time. The addition of a sixth workday for men doing moderately heavy work caused a great increase in absenteeism.

A study found when at the beginning of World War II the work- week was changed from 5 to 6 days, there was a decided increase in absenteeism for women. This change, however, did not alter the absenteeism rate materially for men.

(vi) Rest Pauses:

Management rarely encourages men to take time out for smokes and rest pauses or has permitted lunching during working hours and found the practice detrimental to production. Management personnel criticize existing rest pauses on the grounds of appearance to customers, crowded elevators, crowded coffee shop, and overstaying the period.

Rest pauses have brought about increases in production of 8 to 20 per cent. It is not easy to determine the extent to which the rest pause improves motivation and the extent to which it contributes to the alleviation of fatigue, since these two ‘factors interact in their effect on performance and are hard to distinguish. If authorized rest pauses are not allowed, unauthorized rests will be taken by workers to suit their own convenience. Rest pauses are probably desirable in every type of work.


In heavy muscular work pauses are particularly desirable and should be frequent. Recovery from fatigue is quite rapid at the start of a rest period, but then recovery is slower and extends over a rather long period of time before normalcy is reached. The rest following work must be sufficient to permit complete recovery, for otherwise the remaining fatigue will require relatively longer pauses in subsequent periods. In general, rest pauses provide for recovery as well as resistance to future fatigue.

(vii) Coffee Break:

Managements complain that the coffee break lasts too long. The reason why employees take longer coffee breaks than management wants them to differs from one situation to another, but often it will be lack of interest in the job. Management has more often tacked the immediate problem by administering or policing the coffee breaks instead of concerning itself more with the underlying problem of positive motivation toward work. Some admit improved production due to rest pauses and still oppose coffee time because it ‘disrupts things’ Many executives believe that breaks are essential in order to reduce office fatigue.

If properly administered, it will lessen immediate strain that comes from prolonged and monotonous physical and mental work. Coffee breaks were introduced mainly during and after World War II. On the whore they bring desirable effects. The favorable effects of coffee- break are reduction in worker fatigue, improvement in moral, increased productivity, lower accident rate, and lower employee turnover.

(viii) Location of Rest Pauses:

Rest is most beneficial to output if scheduled just prior to the first drop in production. A rest break should be put there. One should then accumulate new data and schedule another rest period just prior to the next drop in production. It is desirable to give employees a chance to share in the decision as to when they are to take rest pauses and what they are to do during the pause. At the very best, distribution and length of rest periods is in part a trial and error process.


No single schedule for any place of business exists, nor is there any static schedule for all kinds of work. In general, the duration of the rest period should be anywhere from 5 to 20 minutes. Management should schedule the pause to allow the completion of integral work sequences. Pauses should be more frequent near the end of the day. The longer the working span, the longer and more frequent should be the rest period.


Every year millions of industrial accidents occur worldwide causing immense suffering to the accident victim, their family and enormous loss to the organization apart from being a loss to the economy of the individual countries. Considering the human sufferings and economical loss due to the accidents in industries, it becomes imperative on the part of everyone to prevent such accidents by removing or controlling the hazards in industries.

Despite advances in accident prevention techniques and providing safe, and healthy working environment to the industrial workers, safety at work still needs to find a complete solution. Accident prevention does not lie on devising safe machines alone but also on improving the knowledge, skill, attitude and morale of the workers. Accident prevention programs must concentrate both on unsafe conditions in industries and unsafe acts committed by the workers.

Engineering revision and administrative control are primarily remedies to unsafe conditions, whereas safety education alone is the remedy for correcting unsafe acts of the workers. Safety education means the process of educating in safety; a systematic instruction and development of character or mental powers of workers in safety.

Causes of Accidents:

Heinrich found that 98 per cent of the accidents were caused by either unsafe actions or unsafe mechanical or physical conditions or both and that they could be prevented by correction of the unsafe acts and conditions.

The basic theory of accident prevention may be briefly stated as:

Injury occurs only as the result of an accident;

An accident occurs only as a result of unsafe act or unsafe conditions or both

Unsafe actions or unsafe mechanical or physical conditions exist only because of faults on the part of persons; and

Faults of persons are inherited or acquired from the environment

The reasons or causes for the faults are:

(a) Anatomical or physiological characteristics’

(b) Improper psychological characteristics;

(c) Lack of knowledge or skill and

(d) Improper mechanical and physical environment.

Thus in every accidental occurrence, there is always a chain of events which occurs it logical and fixed order. Each link in the chain is dependent upon the preceding link. TI is known as the Heinrich theory of chain of injury occurrence.

According to Heinrich, the three underlying principles of accident prevention are,the creation and maintenance of interest, fact finding, and action based on the facts.

The five steps of industrial accident prevention proposed by him are:

1. Organization,

2. Fact finding,

3. Analysis,

4. Selection of remedy and

5. Application of remedy.

Unsafe Actions:

Unsafe actions are generally classified under the following groups:

(a) Operating without authority;

(b) Operating or working at unsafe speed;

(c) Making safety devices inoperative;

(d) Using unsafe equipment using hands instead of equipment or using equipments unsafely;

(e) Unsafe loading, placing, mixing, combining, etc.;

(f) Taking unsafe position or posture;

(g) Working on moving or dangerous equipments; and

(h) Failure to use safe attire or personal protective devices.

The unsafe acts may be the result of lack of knowledge or skill on the part of the worker, certain bodily defects and wrong attitudes. It has been established that more accidents caused due to improper attitudes than due to ignorance or bodily defects.

Some of wrong attitudes are:

Wrong Attitudes:

(a) Negligence towards use of safety appliances;

(b) Absent mindedness;

(c) Over-confidence or temptation to show off;

(d) Violent temper;

(e) Nervousness;

(f) Lack of interest in the job;

(g) Disregard for safety of others;

(h) And Fatalistic view of life.

The unsafe mechanical/physical conditions

The unsafe mechanical/physical conditions are classified as under the following groups:

(a) Inadequately guarded or defective machines;

(b) Hazardous arrangements and processes;

(c) Unsafe illumination;

(d) Unsafe ventilation;

(e) Unsafe dress or apparel;

(f) Unsafe methods, planning, etc.

The unsafe conditions can be corrected by:

(a) Providing proper guards to the dangerous parts of the machines;

(b) Removing defects from machines by regular and constant check-ups and inspection;

(c) Maintaining proper plant lay-out and house-keeping;

(d) Making provision for adequate lighting, and

(e) Preventing workers from working with loose clothes.

Prevention of Accidents:

As the target groups are the industrial workers having the technical knowledge and ability to read and write, the safety education model has been selected in the form of self-instructional modules, which provide for evaluating and practicing the awareness expected to develop their awareness on safety, to apply them in practice.

Even though there are many training models available, safety education modules are suggested to be the best for achieving of larger tasks since it is a formalized and complete learning package containing all learning resources within each module including detailed instructions in performing the tasks. These safety education modules are well suited when an education program is developed for large number of trainees and need for repeating them many times.

Training programs yield perceptible and significant overall improvement and provide a favorable attitude, which is necessary constituent of long-term changes in behavior.

Three safety education program modules were designed covering general areas of safety, special areas of safety and industry specific areas of safety separately.

Effectiveness of the designed safety education program is measured by implementing it on the workers of the selected industries who had already undergone similar safety education programs in their respective industries by the increase in the level of awareness of the industrial workers with reference to the designed safety education program i.e. by identifying the difference between the post-test and pre-test scores on safety awareness.

Accident Preventive Measures:

The accident preventive measures can be grouped as follows:

1. Plant Safety Inspection:

Safety inspections constitute one of the principal means of locating accident causes. They help in determining the prior measures necessary to guard against hazards. Detecting unsafe conditions and correcting them promptly is one of the best ways of demonstrating a management’s interest and sincerity in accident prevention.

2. Job Safety Analysis:

Job safety analysis is a procedure of analyzing job, for the specific purpose of finding the hazards in each step in the job and developing safety precautions to be adopted. This is best done at the stage of planning. However, the technique can be applied at any state. In fact it is one of the most important means of discovering hazards in an existing system.

3. The Management System:

The root causes of accident often related to the management system and other operational problems. They may be due to management policies, procedures, supervision and its effectiveness, training, etc.

4. Accident Investigation:

Immediate investigation of all accidents is necessary to find out the causes and getting them corrected. Accident investigation should not be a fault-finding exercise but a fact finding one. Discovering accidents includes investigation of all the causes of previous accidents, recording of all the facts concerning each accident, analyzing and tabulating the same, inspection of all the tools, equipments, machines at regular intervals.

5. Controlling Environmental Causes:

It consists of checking of plans, blue­prints, purchase orders, proper maintenance, inspection to detect defects in plans and materials, correction of defects, formulation of safe procedures, suitable layout and equipment for good house-keeping, improvement of illumination and ventilation, safe dress or apparel or personal protective devices. Safety management also includes identifying and changing hazardous working conditions as well as evaluating the effectiveness of safety and health efforts.

6. Controlling Behaviorist Causes:

It deals with physiological and psychological factors such as job analysis, job training, supervision, discipline, personal work, physical examination, proper placement of workers.

7. Safety Education:

Safety education is vital for all accident prevention work in industries. All accident- prevention work, whether or not it is educationally intended, is nevertheless educational in its effect upon the individual employee whom it necessarily involves.

That this is true is clearly indicated by evidence that well- trained and careful men may avoid injury on dangerous work and that untrained and careless man may be injured under the safest possible conditions. The safety- educated person is more likely to regard an accident as being predictable, preventable, and non-accidental.

Safety education plays an important role in the preventive processes. As knowledge increases, one’s behavior becomes more intentional, so that unanticipated events are less likely to result in injury. Part of the role of safety education is to increase knowledge, thereby decreasing the proportion of unintended behavior and increasing the level of anticipation, and the possibility of avoiding danger. The safety training is one piece of the solution to perform safe work practices and a tool for motivating the employees to change.

Safety education in industries suffers from lot of defects primarily they are not tailor made to suit the selected industry. There are many unwanted safety areas in the safety education program that need not be educated at all to the workers of the selected industry.

In many cases there are possibilities of leaving out important safety areas related to the selected industry. Moreover, the contents also do not match the needs and requirements of the workers. Hence it was decided to design an exhaustive safety education program that can be utilized by any industry by adapting them unwanted and unrelated safety areas of the designed safety education program.

The safety education methods should emphasize on the need to report hazardous conditions and practices. Specific hazards of the employee’s job and methods to avoid them, the procedures, precautions, safeguards and personal protective equipments necessary to protect the workers from the hazards of the job and information about actions to be taken by the workers in the emergency situations.

8. Supplementary Activities:

The supplementary activities consist of measures such as:

(a) Plant advertising media such as posters and pictures, plant bulletin boards, plant newspapers, messages in pay envelopes, display of interesting objects, signs of and slogans, exhibitions and film, radio T.V. etc.

(b) Employee participation in safety campaigns and contests, safety meetings and safety stunts, first-aid training, plant fire-brigades, plant inspection, accident investigation, job safety analysis, safety committees, safety suggestion systems.

(c) Standardization of safety activities like laying down of official, semi-official, and unofficial standards for safe construction and maintenance of certain types of industrial equipment, hygienic practices, personal protective devices and codification of safety rules and regulations.

(d) Safety education through audio-visual aids like newspapers, posters, bulletin boards etc., and safety training courses for top and middle management executives, supervisory personnel, trade union officials and for the rank and file workers.

(e) Research in technical, medical, psychological, and statistical aspects of safety to find the effects of psychological, physiological, pathological, environmental and technological factors on health and safety

A sound accident prevention policy can be successful when:

It receives full co-operation of trade union leaders to guide and motivate workers to adopt safe practices;

Exert social pressure on employers to obtain their active involvement in safety;

Create consciousness of cost and hence realization that accidents are to be avoided to be able to face competition;

Improve on the type, quality and availability of personal protective equipments suitable for Indian conditions;

Introduce some incentive schemes for safety performance as responses in certain cases have been excellent;

Extend propaganda so that every worker and his family realize the hazards in his profession and that his safety depends a lot on him.