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Health & Safety Management
Occupational Health & Safety
24-Jun-15
Preston.edu.pk
MuhammadUmer Aziz

Q1: Write a note on the law related with Occupational Health, Safety and Management at
Pakistan.
Answer
The total labor force of Pakistan is 54.92 million, 33 percent of total population is associated
with labor work. This makes Pakistan’s 9th principal nation in the globe in terms of the
volume of its work force in 2010.
Occupational Safety and Health issue has become focus of workers organizations and media
in recent past in Pakistan when in two factory fires more than 325 workers lost their lives in
the month of September 2012. These accidents were the worst industrial accidents happened
in recent history. OSH has never been a priority of the governments in Pakistan nor has it
been understood and addressed properly by the trade union movement. Education on OSH
issues has remained a weak point of the trade union movement in Pakistan. Although
Pakistan has labor laws underlying satisfactory measures to be taken for safe working
conditions for workers but implementation on such laws has been very weak.
Majority of the workforce in Pakistan is illiterate and not trained in occupational safety and
health. Moreover OSH is not included in any curricula in Pakistan. The number of
occupational health physicians and nurses is far less compared to the total workforce in
Pakistan. This means that occupational health system is not established in the country.
The only governmental institute that trains workers about OHS in Pakistan is “Centre for the
Improvement of Working Conditions and Environment”. This center was established in
1988, in Lahore, Pakistan jointly by the Punjab’s Province Directorate of Labor Welfare,
Finnish Institute of Occupational Health and ILO.
Although, the governments had proposed OHS ombudsman and tripartite monitoring councils
in the Labor Policy 2001 and 2010 but so far no steps have been taken in this regard.
Additionally, Factories Act 1934 gives monitoring power to the district magistrate of each
district but in actual there is no trained staff to carry on such monitoring. For example Punjab,
which is the largest province of Pakistan, only has 2 technical inspectors of factories and one
industrial hygienist for the monitoring of 36 districts of Punjab.
Also Factories Act 1934 is not applicable to the enterprises employing less than10 workers.
It does not give coverage to the workers in the agriculture sector, informal/home-based and
seasonal workers. Whereas the role of inspecting staff of Labor and Human Resource
department should not be only prosecuting but to give an advisory services to the
management as well.
There is no independent legislation on occupational safety and health issues in Pakistan. The
main law, which governs these issues, is the Chapter 3 of Factories Act, 1934. All the
provinces, under this act, have devised Factories Rules. The Hazardous Occupations Rules,
1963 under the authority of Factories Act is another relevant legislation. These rules not only
specify some hazardous occupations but also authorize the Chief Inspector of Factories to
declare any other process as hazardous.

The other related laws are:
• Dock Laborers Act, 1934
• Factories Act 1934
• Mines Act, 1923
• Workmen Compensation Act, 1923
• Provincial Employees Social Security Ordinance, 1965
• West Pakistan Shops and Establishments Ordinance, 1969
• Boilers and Pressure Vessels Ordinance, 2002
The OSH laws in Pakistan mainly cover the formal sector manufacturing industries. The
Factories Act, 1934, the main law containing OHS provisions is applicable to manufacturing
enterprises employing 10 or more workers. In addition, the Mines Act, 1923 covers the
mining sectors. Other sectors are either not covered under OSH or the coverage is very
limited.
Provisions under the Factories Act, 1934
Chapter 3 of the Act has general provisions on health and safety at the workplace. Provincial
governments are allowed to make rules under this Act and inspectors under this Act also have
discretion in defining the rules. Chapter 3 talks about various safety arrangements. This list is
being provided just to show how carefully labor law covers these issues.
Table 1
• Cleanliness • Disposal of wastes and effluents
• Ventilation and temperature • Dust and fume
• Artificial humidification. • Overcrowding
• Lighting • Drinking water
• Latrines and urinals • Spittoons
• Precautions against contagious or infectious
disease
• Compulsory vaccination and inoculation
• Power to make rules for the provision of
canteens
• Welfare officer
• Precautions in case of fire • Fencing of machinery
• Work on or near machinery in motion • Employment of young person’s on dangerous
machines
• Striking gear and devices for cutting off power • Self-acting machines
• Casing of new machinery • Prohibition of employment of women and
children near cotton openers
• Cranes and other lifting machinery • Hoists and lifts
• Revolving machinery • Pressure plant
• Floors, stairs and means of access • Pits, sumps, opening in floors, etc.
• Excessive weights • Protection of eyes
• Power to require specifications of defective
parts or tests of stability
• Safety of building, machinery and
manufacturing process
• Precautions against dangerous fumes • Explosive or inflammable dust, gas, etc.
• Notice of certain accidents

Provisions under Mines Act 1923:
1. Conservancy
2. Canteens
3. Shelters
4. Medical appliances
5. First-aid rooms
6. Powers of Inspectors when causes of danger not expressly provided against exist
when employment of persons is dangerous
7. Notice to be given of accidents.
8. Power of Government to appoint court of inquiry in cases of accidents.
9. Publication of reports
Q2: Explain the Health, Safety and Management practices.
Answer
Approved Codes of Practice (ACOP) to the Management of Health and Safety at Work
Regulations (MHSWR) outlines five elements of successful management practice.
Planning:
There should be an efficient & effective management system to implement health
and safety policy which is proportionate to the hazards and risks.
Risk assessment must be done, by adopting a systematic approach, to decide on
priorities & to set objectives for eliminating or reducing risks, also developing
performance standards for the completion of risk assessment and for the
implementation of preventative and protective measures. Different facilities,
equipment and processes are used to eliminate risks.
Organization:
Employees and representatives must be the part of risk assessment and deciding on
preventative and protective measures and putting them into the practice in the
workplace.
There must be flow of communication and consultation, the employer must be
knowledgeable about health and safety information and have good communication
with employees and their representatives in this regard. Good communication
assures the effective implementation. Those who carry risk assessments are
competent if they have more information about Health and Safety; they can also
seek help where necessary.

Control:
Elucidate the health and safety responsibilities, ensuring that the activities of
everyone are well coordinated. Everyone should comprehend his responsibilities
and how to fulfill them effectively.
Standard must be set to judge performance. It is important to reward those who
perform effectively, while take action to improve poor performance. New learners
or people new on job must be supervised by on the ball person.
Monitoring:
Employer must check that, how they are changing the environment of health and
safety in the workplace? Whether is it a positive or a negative change?
Inspections should be made to check the effectiveness of functioning of health and
safety management system and preventative and protective measures. Satisfactorily
investigating the causes of incidents and accidents to ensure that proper action is
taken, lessons are learnt and long-term objectives are introduced. There must be a
record of monitoring and its results for future use.
Review:
Monitoring helps to take a remedial action in good time. To make the entire system
effective, there is a need to review health and safety management system.
Figure 2.1: key elements of successful health and safety management
_____________________________________

Q3: Write a note on the safety signs classification and principal requirements of safety signs
and signal at the works place.
Answer
Safety sign is defined as,” a sign that gives a message about health or safety by a combination
of geometric form, safety color and symbol or text, or both”.
Health and Safety ( Safety Signs and Signals) Regulations 1996.
These regulations apply to all workplaces, including offshore installations and work activities
where people are employed, but exclude signs and labels used in connection with the supply
of substances, products and equipment or the transport of dangerous substances.
The system for signs and signboards is based on the familiar “traffic light” color:
 Red for Prohibition
 Yellow for Caution
 Green for Positive action
A fourth color, blue, is used for mandatory signs and to convey information such as the
location of a telephone.
The shapes of the signboards are standardized:
• Discs for prohibitions and instruction
• Triangles for warnings
• Squares and rectangles for emergency and informative signs.
Safety signs classifications
Prohibition Signs:
These are circular with a red band enclosing a crossed-out symbol on a
white background. Few examples of prohibition signs are as under.
Warning Signs:
These signs are triangular in shape with a yellow background and black
borders, symbols and texts.

Mandatory Signs:
These are circular in shape, incorporating a white mandatory symbol
and/or text on a blue background.
Safe Condition or information Signs:
These are indicated by green square or rectangle with symbols and
lettering in white.
Acoustic signal means a coded sound signal which is released and transmitted by a device
designed for that purpose, without the use of a human or artificial voice.
Emergency escape or first-aid sign means a sign giving information on emergency exits or
first-aid or rescue facilities.
Hand signal means a movement, position, or both, of the arm, hands, or both, in coded form,
for guiding persons who are carrying out maneuvers which constitute a hazard or danger for
persons at work.

Illuminated sign means a sign produced by a device made of transparent or translucent
materials which are illuminated from the inside or the rear in such a way as to give the
appearance of a luminous surface.
Information sign means a sign providing information other than that referred to in
prohibition, warning, mandatory or emergency escape or first-aid signs.
Mandatory sign means a sign requiring specific behavior.
Prohibition sign means a sign prohibiting behavior likely to incur or cause danger.
Safety color means a color to which a specific meaning is assigned.
Safety or health signs means signs referring to a specific object, activity or situation and
providing information or instructions about safety, health, or both, at work by means of a
signboard, a color, an illuminated sign, an acoustic signal, a verbal communication or a hand
signal.
Supplementary signboard means a signboard used together with one of the signs covered
by the definition of “signboard” and which gives supplementary information, including,
where appropriate, information in writing.
Signboard means a sign which provides specific information or instructions by a
combination of a geometric shape, colors and a symbol or pictogram, without written words,
which is rendered visible by lighting of sufficient intensity;
Symbol or pictogram means a figure which describes a situation or requires specific
behavior and which is used on a signboard or illuminated surface;
Verbal communication means a predetermined spoken message communicated by a human
or artificial voice;
Warning sign means a sign giving warning of a hazard or risk.
Principal Requirement
If risk cannot be controlled or avoided then safety signs must be provided where risk
assessment is made under MHSWR. Sign is not required where risk is negligible or where
risk cannot be reduced using signs. Safety signs include, hand signals, pipeline markings,
acoustic signals and illuminated signs.
Text should not be incorporated into a signboard. If a text explanation is deemed necessary,
then it should be incorporated by means of a supplementary signboard as shown in the
diagrams below

Where doubt could exist as to the meaning of a graphical symbol used on a safety signboard,
a supplementary signboard containing appropriate text should supplement the safety
signboard. However if the meaning is clear by use of a pictogram or symbol alone, then a
supplementary signboard should not be used. The following are examples of signboards
incorporating supplementary signboards to clarify the meaning
Combined Signboards:
Each safety signboard and associated supplementary signboard should be used to convey only
one safety message. Composite signs giving more than one safety message should not be
used. Graphical symbols should not be combined to convey more than one safety message.
For example, if a mandatory instruction to wear safety helmets and safety goggles is required,
two signboards should be used. The safety helmet and safety goggles should not be combined
as one graphical symbol.

A supplementary signboard placed with a safety signboard should not be used to convey a
second safety message. For example, if a safety signboard indicating warning is to be
accompanied by an mandatory action, either two separate signboards should be used or the
separate signboards (and supplementary signboards) can be combined on one carrier.
Safety signs must convey message, for instance, fire exit, fire fighting and fire alarm signs.
Fire exit sign must incorporate the “running man” pictogram. The display of sign (fire exit
without the pictogram is illegal).
Training must be given to employees, so that they can understand the safety signs, and signs
must be maintained. Use of traffic signs to regulate traffic within workplaces where required
to regulate traffic. For instance, while constructing fly-over.

Marking pipe work containing dangerous substances, use of hand signals for mechanical
handling and directing vehicles. Locations where people may slip, or fall from heights, or
where there is low headroom may need to be marked to meet the requirement of WHSWR.
Sites where 25 tons or more dangerous substances are stored need to be marked in
accordance with the dangerous substance. Fire alarm signal must be continuous, where
evacuation from a building is needed.
_______________________________
Q4: Write a note on machinery guarding and its classifications.
Answer
Machinery hazards:
“A machine is an apparatus for applying power, having fixed and
moving parts, each with definite functions.”
For primary output functions there are operational parts of machine e.g drilling a hole.
For power and motion there are non-operational parts e.g drives to motor.
Prime mover and transmission machinery are the functional parts of a machine.
Prime mover provide mechanical energy derived from steam, water, wind, electricity etc. e.g
engine & motor.
Transmission machinery transmits motion of prime mover to any machine. For example,
shaft, drum, pulley, coupling, wheel, and clutch.
Machinery related injuries includes coming into contact with machinery or being trapped
between the machinery, being struck by or becoming entangled in motion in the machinery,
being struck by the parts of the machinery ejected from it and being struck by the material
ejected from the machinery.
Design of machinery is associated with machinery related hazards.
Machinery Guarding
Definition:
“To protect the operator and other employees in the machine area from hazards such as
those created by point of operation, ingoing nip points, rotating parts, flying chips and
sparks.”
Guards shall be affixed to the machine where possible and secured elsewhere if for any
reason attachment to the machine is not possible. The guard shall be such that it does not
offer an accident hazard in itself.

The guarding device shall be in conformity with any appropriate standards therefore, or, in
the absence of applicable specific standards, shall be so designed and constructed as to
prevent the operator from having any part of his body in the danger zone during the operating
cycle. Regulations (Standards - 29 CFR).
Machinery guards are classified in order of relative safety.
Fixed guards: The most effective form of guard is the fixed guard. They have no moving
parts associated with them, also do not depend on any other mechanism of machinery. They
prevent access to danger point or area when installed.
Figure 4.1: A fixed guard on a power press completely encloses the point of operation.
They are principally used to prevent access to non-operational parts and may take the form of
solid casting, sheet metal (minimum 18 SWG- 1.22mm), perforated or expanded metal, ‘weld
mesh’ (minimum 14SWG), safety glass panels or polycarbonate panels.
Safeguarding Action: Provides a barrier
Advantages: Can be constructed to suit many specific applications. In-plant construction is
often possible. Can provide maximum protection Usually requires minimum maintenance.
Can be suitable to high production, repetitive operations.
May interfere: May interfere with visibility. Can be limited to specific operations. Machine
adjustment and repair often require its removal, thereby necessitating other means of
protection for maintenance personnel.
Interlock Guards: These guards have movable part so connected with the machinery
controls that
The part of machinery cannot be set in motion until the guard is closed. Before
opening the guard power is switched off and motion braked to allow access to
the dangerous parts. Access to danger point or area is denied while the danger
the danger exists.
An interlocked guard may use electrical, mechanical, hydraulic, or pneumatic power or any
combination of these. Interlocks should not prevent "inching" by remote control if required.
Replacing the guard should not automatically restart the machine. To be effective, all
movable guards should be interlocked to prevent occupational hazards.

Figure 4.2: Interlocked guard on automatic bread bagging machine
An interlocking guard is the moving guard which, in the closed position,
prevents all access to the dangerous parts. The operation cannot be started,
until the guard is fully closed and the guard cannot be opened until the
dangerous moving parts have come to rest.
Reliability and maintenance of interlocking guards is important to achieve
same level of safety as fixed guards.
Methods of interlocking guards: Mechanical, Electromechanical, Pneumatic (compressed
air), Hydraulic (electro), Key exchange (electrical), Simple electrical.
Automatic Guards: These guards depend upon the mechanism of the machinery and operate
so as to remove physically from the danger area, any part of a person exposed to danger. It
incorporates a device so fitted in relation to the dangerous parts that the operator is
automatically prevented from coming into contact with same.
Power presses, press brakes and certain types of guillotine uses this system of guarding.
Disadvantages: Risk of injury to the operator as a result of the sweep away motion. The
linkages to the motion must be rigidly connected as they can become loose through constant
use. When the linkages become worn the guard is often racing the tools to maintain safe
operation. They need extensive maintenance and frequent inspection.
Distance guards: This guard doesn’t entirely enclose a danger area or point but which place
it out of normal reach. The guard may incorporate a tunnel, fixed grill or rail positioned at
sufficient distance so that access to the moving parts cannot be gained except through a
intentionally unsafe act.
Figure 4.3 Distance Guard

Adjustable Guards: These guards incorporate an adjustable element which, once adjusted,
remains in that position during a particular operation. This is the least reliable form of guard
in that it requires the operator to adjust same to the safe position prior to the operation of the
machine. Used in drilling machinery and certain types of wood working machinery, such as
circular saws and band saws.
Fig: 4.4 Adjustable saw on power press and horizontal bandsaw respectively
______________________________
Q5: Give the classification of fire fighting appliances and equipment.
Answer
Fire is a chemical reaction that requires three elements to be present for the reaction to take
place and continue. The three elements are:
1. Heat or an ignition source
2. Fuel
3. Oxygen
These three elements typically are referred to as the “fire triangle.” Fire is the result of the
reaction between the fuel and oxygen in the air.
Fire Classifications: Fires are classified as A, B, C, D or K based on the type of substance
that is the fuel for the fire, as follows:
Class A: fires involving ordinary combustibles, such as paper, trash, some plastics, wood and
cloth. A rule of thumb is if it leaves an ash behind, it is a Class A fire.
Class B: Fires involving flammable gases or liquids, such as propane, oil and gasoline
Class C: Fires involving energized electrical components

Class D: Fires involving metal. A rule of thumb is if the name of the metal ends with the
letters “um,” it is a Class D fire. Examples of this are aluminum, magnesium, beryllium and
sodium. Class D fires rarely occur in the roofing industry.
Class K—fires involving vegetable or animal cooking oils or fats; common in commercial
cooking operations using deep fat fryers
Fire Extinguishers
There are different types of fire extinguishers designed to put out the different classes of fire.
Selecting the appropriate fire extinguisher is an important consideration. The wrong
extinguisher actually may make a fire emergency worse. For example, failing to use a Crated
extinguisher on energized electrical components may endanger workers by causing the
extinguishing material to be electrified by the energized components that are on fire. C-rated
fire extinguishers put out the fire by using a chemical that does not conduct electricity.
Extinguisher Color code
Water Red
Foam Cream
Carbon dioxide Black
Dry chemical powder Blue
Vaporizing liquid Green
Table 5.1 Grouping and color coding of fire appliances
Portable fire-fighting appliances: These appliances are operated by hand, it uses internal
pressure to expel the extinguishing medium and directed on fire. Pressure can be stored, or
obtained by chemical reaction or by release of gas from the cartridge. The maximum mass of
portable extinguisher in working order is 23 kilograms.
1) Water appliances
These appliances reduce the temperature within the fire, and slow down the rate of
combustion and prevent ignition from taking place. Steam is produced, which has
blanketing effect, reducing the amount of air to maintain combustion.
2) Foam appliances
It prevents further air from reaching the combustion area or seat of fire. In case of
flammable liquids, foam forms a barrier floating over the burning surface, reducing
the evaporation rate of liquid and stopping the entrance of oxygen to maintain
combustion.
3) Carbon Dioxide appliances
When these appliances are operated, produce a snow which is converted to gas in the
fire. It slows down the rate of combustion, reduces the availability of oxygen to
combustion area.
4) Dry chemical powder appliances
These appliances contain a specific powder mixture which interferes with the
combustion process, reducing the combustion rate until fire us extinguished.

5) Vaporizing liquid appliances
These appliances contain halogenated hydrocarbons, such as Halon. They produce
heavy vapor, when operated for fir extinguishing. Vapors are produced due to
exclusion of oxygen and interference with chemical combustion reactions.
The following table illustrates the types of extinguishers, fire classes for which each is
used and the limitations of each extinguisher
Fire Extinguisher Type Class of fire it extinguishes Extinguisher limitations
Dry Chemical (multipurpose) A, B, C Generally good for use in roofing
industry
Foam—alcohol-resistant
and aqueous film-forming foam
(AFFF) types
B Expensive; effective on Class B
only; limited shelf life; generally
not needed in roofing industry
Water A Good only for Class A fires
Metal X D, B,C Expensive must be kept dry,
ineffective on A
Carbon Dioxide B,C If used in confined areas will create
oxygen deficiency; not effective in
windy conditions. Can cause
frostbite during discharge.
Halon B,C Expensive not effective in windy
conditions, toxic gasses may be
released in extremely hot fires
because of decomposition
PotassiumAcetate K Expensive wet chemical
extinguisher for commercial
cooking operations using oil and
gas
Table 5.2
In situ fire-fighting equipment
This form of fire-fighting equipment is permanently installed in building and takes the form
of hose reels and sprinkler system.
1) Hose reel appliances: It is a fixed fire-fighting installation comprising a coil of
25mm internal diameter (ID) flexible hose directly connected to a rising water main.
The complete installation consists of either a wet rising main of dry riser and a
landing valve or the fire hydrant. Wrought steel pipe is used of internal diameter not
less than 100mm for installation of main.
Figure 5.1 Hose wheel appliance

Wet rising main should contain water all times and be directly connected into the fire main
with the water at fire main pressure; they may be subject to damage by frost if not adequately
protected.
The pipe has to be charged with water prior to use of the dry rising main. This can be done by
means of pump or opening it out into the fire main.
2) Sprinkling system: This system detect and extinguish or control a fire in early stage.
It includes an overhead piping system with sprinkler heads fitted to the system at
specific points.
Figure 5.2: Sprinkler system
The water is supplied from a header tank or water main. The sprinkler head opens at a
specific temperature and release water. Water supply must be automatic and not
exposed to risk of freezing. This system can be arranged to operate an alarm on initial
release of water.
There is a fire alarm system to warn the occupants at the early stage when fire sets in a
building. This system is required in commercial, industrial and public buildings. People must
be taught what to do when they listen, a fire alarm or discover a fire in the building.
___________________________
Q6: Write a note on the portable electrical appliances and hazards associated with them.
Answer
Anything that can be connected to 13 ampere socket is called portable electric appliance. For
example, kettles, drills, vacuum cleaners, lamps and word processors. In addition, 100V
industrial portable electric equipment should be considered as portable appliance.

Figure 6.1 Portable electric appliances
Almost one quarter of the accidents of electric shocks are associated with different types of
portable electric appliances. It is the duty of the employers to check and examine the
electrical equipment.
Safety of electric appliances: Insulation and earthing of the appliance is mandatory, to
protect the operator from the risk of electric shock. Insulation must be high resistant at high
voltages, and earthing must offer a low impedance to any potentially high fault current.
There should be two levels of protection for the operator, and this result in two levels of
appliance.
Class1 appliance: incorporates both earthing and insulation (earthed appliances)
Class 2 appliance: are doubly insulated.
Testing of class1 and class2 appliances differ according to the type of protection provided.
Testing should be taken on regular basis and should contain the following:
 Inspection of any visible signs of damage to or deterioration of the casing, plug
terminals and cable sheath.
 And earth continuity test with a substantial current capable of revealing partially
severed conductor; and
 High-voltage insulation tests.
The control system should includes, identification of the specific responsibility for appliance
testing, maintaining the inventory record of all portable appliances and test results, labeling
the appliances with serial numbers and dates of inspections.
Any appliance that fails the tests must be removed from the service.
Testing of portable appliances: Portable appliance testing (PAT) is the term, used to
describe the examination of electrical appliances and equipment, to ensure they are safe to
use. Most electrical safety defects can be found by visual examination but some types of
defect can only be found by testing. However, it is essential to understand that visual
examination is an essential part of the process because some types of electrical safety defect
can't be detected by testing alone.
There are two types of tests for PAT device, namely:
Earth bond test: This applies a substantial test current, typically around 25 amperes down
the earth pin of the plug to the earth test probe, which should be connected by the operator to
any exposed metal work on the casing of the appliance under test. The resistance of the earth
bond is indicated by the PAT device.
Insulation test: This applies a test voltage, normally 500V direct current, between the live
and neutral terminals bonded together and earth, from which the insulation resistance is
indicated by the PAT device.
Other tests include, Flash test, load test, operation test, earth leakage test and fuse test.

For earthed class1 appliances the following tests are undertaken:
1. Earth bond test
2. Insulation test
3. In some cases, flash test
For Double-insulated class2 appliances following tests are undertaken:
1. Insulation
2. Flash
Environments that require testing: In clause 150 of the Regulation, the environments that
require testing include those which expose the equipment to moisture, heat, vibration,
mechanical damage, corrosive chemicals or dust. Examples include wet or dusty areas,
outdoors, workplaces that use corrosive substances, commercial kitchens and manufacturing
environments. Note that due to the nature of the work conducted in some laboratories and
workshops, they may be considered a higher-risk operating environment. Assessment of your
workplace should be carried out to determine if it is considered a higher-risk operating
environment under the WHS Regulation.
Hazards associated with portable electric appliances
Electricity can kill or severely injure people and cause damage to property. However, you can
take simple precautions when working with or near electricity and electrical equipment to
significantly reduce the risk of injury to you, your workers and others around you.
The main hazards of working with electricity are:
 electric shock and burns from contact with live parts
 injury from exposure to arcing, fire from faulty electrical equipment or installations
 explosion caused by unsuitable electrical apparatus or static electricity igniting flammable
vapors or dusts, for example in a spray paint booth
Electric shocks can also lead to other types of injury, for example by causing a fall from
ladders or scaffolds etc.
Voltage Response Current
15 volts Threshold of feelings 0.002-0.005 amp
20-35 volts Threshold of pain _
30 volts Muscular spasm(non-release) 0.015 amp
70 volts Minimum for death 0.1 amp
120 volts Maximum for ‘safety’ 0.002 amp
200-240 volts Most serious/ fatal accidents 0.2 amp
Table 6.1: Typical responses to current/ voltage

Heart is the most susceptible to electric shock it disturbs, the heart rhythm, blood flow and its
vital functions. This is the process of ventricular fibrillation the most common cause of death,
it occurs at 0.05 amperes.
First Aid
Electric shock:
 Cardiac massage plus mouth-to-mouth resuscitation until the normal breathing and
heart action return
 Before approaching to the victim, make sure that electric appliance is dead
electrically.
________________________
Q7: What are the principal hazards in Construction Activities?
Answer
There is a wide range of hazards associated with construction. The principal hazards and their
causative factors are given below:
Falls from ladders: Use of incorrect ladder pitch, results in ladder slipping at the base or
falling away at the top. The ‘1 Out: 4 Up Rule’ should always be applied in assessing the
correct pitch of ladder. Falls can also arise from using defective wooden, metal ladders and
overreaching situations.
Figure 7.1

AIHW National Injury Surveillance Unit ResearchCentre for Injury Studies Flinders
University South Australia
3,486 injury incidents due to a fall from a ladder resulted in admission to hospital in the year
to 30 June 2005. The rate of injurious falls from ladders in 2004–05 was 18.5 per 100,000
population. Age-standardized rates of injurious falls from ladders were highest for older
people; for males aged 65 years and older this rate was 73.9 per 100,000 and for females aged
65 years and older this rate was 18.4 per 100,000. Injuries to the elbow and forearm, knee and
lower leg and injuries to the head were the most common principal diagnoses to result from
ladder-related falls.
Falls from working platforms: Unfenced, poorly fenced, defective boarding and absence of
toe boards are contributory factors in falls of people from working platforms.
Figure 7.2 well-designed working platforms
Falls of materials: Objects like bricks, tiles and hammers fall from height cause severe head,
and other forms of injuries. This situation arises due to poor housekeeping on working
platforms. Absence of toe boards, barriers, incorrect assembly of gin wheel, incorrect
hooking, and incorrect slinging of loads, failure to install catching platforms and through
demolition materials being thrown to the ground.
Figure 7.3 Falling objects

Falls from pitched roofs or through fragile roofs: Perhaps this is the most common cause
of fatal accident associated with the construction industry and with those involved in the
maintenance of the buildings. This happens due to, unsafe working practices, use of
inappropriate foot wear, failure to provide verge and eaves protection and to use crawl board
on pitched roofs, together with stacking of roofing material on fragile roofs.
Figure 7.4: working safely on pitched and fragile roof
Falls through openings in flat roofs and floors: This type of accident arises due to the
failure to provide or replace covers to opening or edge protection in opening in flat roofs and
floors during various stages of construction. All covers should be clearly marked to indicate
the presence of an opening below that cover.
Figure 7.5 unguarded vs guarded
Collapses of excavation: Failure to support a trench or excavation properly or in shifting
sand situation, give rise to fatal injuries and asphyxiation. Presence of large quantities of
water arising may be as a result of flash flood or water main bursting also a contributory
factor in collapse. Other reasons includes, practice of stacking building material, such as
pallet loads of bricks, heavy concrete sewer pipe sections and heaps of sand too close to the
edge of a deep open trench.
Figure 7.6 Excavation collapse

Transport accidents: Injuries arising from people falling from vehicles, some of which may
not be designed for carrying passengers, such as dumper trucks, are common. Other accidents
include crushing by reversing vehicle where no banksman is in operation and collision with
defective vehicles.
Figure 7.7: Inadequately operating vehicle leads to accidents
Use of machinery and powered hand tools: Major injuries arise by not guarding the
moving and dangerous parts of machinery, such as power take-offs, wood working
machinery, belt drivers and cooling fans. Other risks include electrocution from uninsulated
electric tools.
Housekeeping: There is a variation in standards of housekeeping in construction. A range of
injuries arise from slips, trips and falls. Management should insure the good standard of
housekeeping.
Fire: Poor fire protection is associated with poor inadequate standards of site supervision,
contribute greatly to the risk of fire.
Personal protective equipment (PPE): Failure of both employers and employees to provide
and use of PPE respectively, leads to major injuries at the workplace.
Work over water and transport across water: Working on bridges exposes the workers to
the risk of drowning. For this reason safety harness must be provided and used at all times.
Transport over water to a particular workplace, further exposes the workers to the risk of
drowning. This may be caused by, over-crowded, defective and inadequate boats. Also,
failure to provide life jackets and other forms of rescue equipment.
Figure 7.8 work over water with no safety

Work involving hazardous substances: Workers are exposed to lead, asbestos, vapors,
dusts, fumes and other dangerous chemical substances in the workplace. Exposure standards
must be managed to prevent any unhappy event. PPEs must be used to prevent inhalation of
dusts and fumes. Air monitoring must be done, where there is probability of presence of lead.
Biological monitoring must also be done where necessary.
Manual handling operations: prolapsed intervertebral discs and hernias are caused by
incorrect handling techniques an attempting to lift loads which are too heavy.
Figure 7.9: manual handling and problems associated with incorrect handling
Work on under-ground services: During excavation, damage to electricity, gas and water
mains can arise. This is due to absence of plan or failure to consult existing site plans prior to
work commencing.
Figure 7.10: underground services
Works in confined spaces: According to confined spaces Regulations 1997 confined space
is defined as,
‘A place which is substantially, though not always entirely enclosed and where there is risk
that anyone who may enter the space could be; injured due to fire or explosion, overcome by
gases, fumes, vapors or the lack of oxygen, drowned, buried under free flowing solids, such
as grain or overcome due to high temperature.’

According to OSHA if oxygen level drops below 19.5 percent in atmosphere it is dangerous.
Work in confined spaces exposes operators to the risk, in particular, of both asphyxiation and
anoxia (Oxygen deficiency), which may be due to the absence of ventilation in these spaces.
Under regulations employers must avoid entry to confined spaces. Ensure employees follow a
safe system of work, such as permit to work system, if entry to confined spaces is
unavoidable and put in place emergency arrangements before work starts, which will
safeguard any rescuers involved.
Figure 7.11: work in confined space and sign board
_______________________________
Q8: Write a note on classification of occupational health risks.
Answer
“Occupational health refers to the identification and control of the risks arising from
physical, chemical, and other workplace hazards in order to establish and maintain a safe
and healthy working environment.”
Or
“The maintenance of the individual worker’s state of wellbeing and freedom from
occupationally-related disease or injury.”
The worker interacts with the workplace through:
 Sensory input- sight, sound, smell, feeling
 Ergonomic factors- posture, task, energy demand.
 Chemical contact- via inhaled air, skin contact
 Physical contact- pressure, vibration, noise, heat, radiant energy, ionizing radiation.
There are three routes of entry of hazardous substances into the body:
 Inhalation
 Skin contact
 Ingestion

Occupational health risks
Physical
All workplaces result in exposure to physical agents which could be harmful, including heat,
noise, vibration, repetitive movements, light and other radiations.
Noise: absorbed through the ear; some very low frequency (infrasound) and ultrasonic sounds
are absorbed directly by the body. Risk includes ‘hearing loss’.
Vibration: received by body in contact with vibration. Risk include ‘vibration-induced white
finger’.
Light: visible, ultra violet and infrared are received by both the eye and the skin. Poor
lighting may also be a workplace health hazard. Risk includes radiation sickness.
Heat: absorbed by all parts of the body. Risk includes ‘heat stroke’.
Cold: cold environments experienced by whole of body; extremities in contact with cold.
Risk includes ‘Frost bite’.
Chemical
Exposure to chemical substances classified as ‘toxic’, ‘corrosive’, ‘harmful’ and ‘irritant’
under CHIP regulations can result in death along with a wide range of chemical poisoning
and occupational cancers. Dermatitis is a classic indication of exposure to hazardous
chemicals.
Biological
Working in hospital laboratories and agriculture expose the workers to bacteria, viruses and
other dangerous micro-organisms, some of which are transmissible to humans. These include
the human version of anthrax, brucellosis, leptospirosis, Legionnaires’ disease and
aspergillosis. Certain diseases like anthrax and brucellosis are transmissible from animals to
humans (zoonoses).
Ergonomic (work related)
Visual and postural fatigue, physical and mental stress and other problematic conditions that
affect people arise due to, excessive and repetitive movements of joints and poorly designed
work layouts and workstations. These include, for instance, writer’s cramp, various ‘beat’
disorders, like beat elbow and beat wrist, and that group of disorders are known as the “work
related upper limb disorders or repetitive strain injury.”
Hernias, prolapsed intervertebral disc (slipped disc), muscle and ligamental strains also come
in this category.
_________________________
Q9: Write a note on the classification of personal protective equipment.
Answer
“Personal protective equipment (PPE) refers to protective clothing, helmets, goggles, or
other garments or equipment designed to protect the wearer's body from injury. The
hazards addressed by protective equipment include physical, electrical, heat, chemicals,
biohazards, and airborne particulate matter.”

The provision and use of PPE is the classic ‘safe person’ strategy. Provided it is worn or used
properly all the time that the person is exposed to hazard, it should give a reasonable level of
protection. However, there are serious limitations in the use of PPE as the sole measure in
protecting people.
Classifications of personal protective equipment
There is a wide range of PPEs available to persons at work.
Head protection: safety helmets, a range of ridding helmet, industrial scalp protector (bump
caps), caps and hairnets.
Figure 9.1: Safety helmet and Hair net
Eye protection: safety spectacles, safety goggles and eye shields.
Figure 9.2: Eye Protection goggle and spectacle
Face protection: Visors (face shield) which can be held in the hand, attached to a safety
helmet or trapped to the head.
Figure 9.3: Visor (face shield) and hand-held shield

Respiratory protection: general purpose dust respirators, positive pressure powered dust
respirators, helmet-contained positive pressure respirators, gas respirators, emergency escape
respirators, air-line breathing apparatus and self-contained breathing apparatus.
Figure 9.4: Respiratory protection
Ear protection: ear defenders, ear muffs, ear plugs, ear valves and acoustic wool.
Figure 9.5: Ear protection instruments
Skin protection: barrier creams and sprays.
Figure 9.6: Barrier cream
Body protection: One-piece and two-piece overalls, donkey jackets, rubber and PVC-coated
aprons, chain-mail aprons, vapor suits, splash-resistant suits, warehouse coats , body warmer,
thermal and weather protection over-clothing, oil skin over-clothing, and high visibility-
clothing, personal buoyancy equipment, such as life jackets.

Figure 9.7: Body protectors
Hand and arm protection: general purpose fiber gloves, PVC-coated fabric gauntlets and
gloves, leather gloves and sleeves, wrist protectors, chain-mail hand and arm protector.
Figure 9.8: hand and arm protectors
Leg and foot protection: safety boots and shoes, wellington boots, clogs, foundry boots,
anti-static foot wear, together with gaiters and anklets.
Figure 9.9 leg and foot protectors
__________________________
Q10:
a) Write a note on the organizational characteristics which influence safety related
behavior.
b) Explain that how the physical state of the hazardous substances has potential for
harm.

Answer
a) Human factors greatly affect the role of organization concerned with health and
safety, the jobs that people do and behavioral factors, such as attitude, motivation and
perception. It also covers particular areas of importance such as ergonomics, the
potential for human error, the systems for communication within organizations,
developing and promoting the right safety culture and the significance of training in
ensuring a safe and healthy workplace.
Human behavior has a direct influence on safety in many aspects of life – at work, in the
home, on the road, in the air and at sea. Evidence drawn from past disasters, such as the
incidents at Flixborough, Kegworth and Moorgate, and the Piper Alpha incident, indicate
that failures in, or inappropriate, human behavior was a significant contributory factor. What
is meant, then, by behavior?
Definition of ‘behavior’
‘Behavior’ is variously defined as:
 how a person conducts himself;
 the demeanor and manners of an individual;
 an observable action of a person.
Behavioral sciences, therefore, are those sciences most concerned with the study of human
and animal behavior. This study allows the formation of general theories based upon the
observation of specific events. The theories are subsequently used to explain observed
events and, in some cases, to predict future events or outcomes. The causes of human
behavior are associated with attitude, personality, motivation and memory, together with
those physical and mental characteristics which constitute a person and his environment.
Human factors cover a range of issues:
 The perceptual , physical and mental capabilities of people and the interaction of
individuals with their job and working environments
 The influence of equipment and system design on human performance
 Those organizational characteristics which influence safety related behavior.
These are directly affected by:
 The system for communication within the organization
 Training systems and procedures in operation
The various aspects of human behaviour are considered below.
Attitude
‘Attitude’ can be defined in a number of ways:
 a predetermined set of responses built up as a result of experience of similar
situations
 a tendency to behave in a particular way in a particular situation;
 a tendency to respond positively (favorably) or negatively (unfavorably) to certain
persons, objects or situations;
 a tendency to react emotionally in one direction or another.
Rokeach (1968) defined ‘attitude’ as ‘a learned orientation or disposition towards an object
or situation which provides a tendency to respond favorably or unfavorably to the object or
situation’.

Motivation
A motivator is something which provides the drive to produce certain behaviour or to mould
behaviour. For example, physical punishment was seen, for many years, to be an important
motivator in terms of molding the attitudes of school children in their formative years and as
a means of deterring criminals from future criminal behaviour. For many people, money is
an important motivator.
Everyone is motivated by the need, for example, to be safe, be warm, have sufficient food,
and belong to a group, such as a family or work group, to achieve things and to have an
ordered life. Needs continually arise and in some cases these needs are satisfied. In other
cases, the needs are not satisfied, which can result in stress, loss of motivation and loss of
self-esteem
Motivation and safety
Important factors for consideration in motivating people to better levels of safety
performance include the following.
Joint consultation
Consultation with workers in planning the organization of work is one of the greatest
motivators from a health and safety viewpoint. Consultation is best undertaken through a
formally established health and safety committee with clearly defined objectives that is
representative of all the people concerned. This committee should meet regularly, publish
agendas and minutes, and implement decisions consistently and in an expeditious manner.
Above all, it must have credibility with the workforce.
Trade union safety representatives and worker-elected representatives of employee safety
have, further, an important role to play in the joint consultation process. It is important that
the role and functions of such people are clearly identified and that they be adequately trained
in the various aspects of occupational health and safety in order to make as constructive a
contribution as possible.
The use of working parties
These can be used to define objectives, including those for health and safety. In certain cases,
small working parties can examine a particular situation, reporting their findings to the health
and safety committee.
Attitudes currently held
Those attitudes currently held by management and workers with regard to safe working are
true indicators of the importance attached to health and safety at work. It is important that
both groups are positively motivated towards success in improving levels of health and safety
performance.
The communications system
Communications systems within the organization should provide information that is
comprehensible and relevant to all concerned. Many people become demotivated by
communications that they find difficult to understand or interpret.

The quality of leadership
Leadership, as with all areas of management, should come from board level if people are to
be adequately motivated towards improved standards of health and safety performance.
Perception
People perceive and gain information through what they see, hear, touch, taste and smell.
Perception is the complex mental function giving meaning and significance to sensations. An
individual is constantly responding in some way to incoming stimuli. These stimuli can be
accepted, rejected, ignored or distorted. It all depends upon whether the stimulus supports or
contradicts the individual’s beliefs, values and attitudes.
Mental and Physical capabilities of people
The employer must assign particular responsibilities to those employees who are capable of
doing that.
Matching the person to the job ensures that he will not be over-loaded and will not make
mistakes.
Physical and mental match is mandatory for the worker to perform a specific tasks, otherwise
he will, not be able to work effectively and efficiently and make mistakes very often.
Human error arises due to inadequate information, lack of understanding, in adequate
design, lapses of attention, mistaken actions, misperceptions, mistaken priorities and
willfulness.
Organizational safety culture
Organizations endeavor to promote an appropriate culture with respect to, for example,
quality management, customer service and sales management. This implies the establishment
and implementation of a range of objectives and means for achieving these objectives,
together with frequent monitoring of the performance of employees to ensure working
practices devised to meet the objectives are being maintained.
The effective development and promotion of health and safety is an important feature of the
health and safety culture of any organization.
Objectives should be set at the highest level and determine the objectives to be set for each
group and subgroup.
Authority and direction To be given responsibility requires being given the necessary
power and authority to implement that responsibility. ‘Direction’ implies the planning and
giving of orders.
Delegation of responsibility senior management is responsible for achieving the overall
objectives, but each group leader is then delegated responsibility for ensuring his group
achieves its objectives.
Accountability Every person delegated responsibility is accountable for his actions to the
person who delegated the responsibility to him.

Division of activities Various activities within the whole are divided into specialist groups in
order to improve efficiency and to give greater control to higher management. Generally,
within the strata of management, authority and responsibility are passed downwards, whereas
accountability is passed upwards.
____________________________
b) Any substance, in gas, liquid or solid form, which has the potential to cause harm, is
referred to as a hazardous or dangerous substance. Such substances include those:
■ Brought directly into the workplace and handled, stored and used for processing (e.g.
solvents, cleaning agents, glues, resins, paints).
■ Generated by a process or work activity (e.g. fumes from welding/soldering, dust from
machining of wood, flour dust, solvents).
■ Generated as waste or residue (e.g. fumes from soldering irons, carbon monoxide from
exhausts).
Substances can be considered hazardous not only because of what they contain (i.e. their
chemical ingredients) but because of the form or way in which they are used at the
workplace.
In addition to their effects on human health, some chemicals also present physical hazards
such as the potential to ignite or support combustion of other substances (oxidizer) and the
potential to explode. The physical, environmental and human hazards of a chemical substance
must be considered when conducting a risk assessment in the workplace.
In what forms do chemicals exist?
Chemicals can exist in the form of:
■ Solids such as dusts, fumes, fibers (e.g. wood dust, bitumen fumes and asbestos fiber).
■ Liquids mists (e.g. liquid bleach and mineral oil mist).
■ Gases, vapors’ (e.g. carbon monoxide gas and solvent vapor.
 How Chemicals Enter the Body:
Inhalation Breathing in contaminated air is the most common way that workplace chemicals
enter the body.
Skin contact Some chemicals, by direct or indirect contact, can damage the skin or pass
through the skin into the bloodstream.
Ingestion Workplace chemicals may be swallowed accidentally if food or hands are
contaminated.
Injection can occur when a sharp object (e.g. needle) punctures the skin and injects a
chemical directly into the bloodstream.
 Effects of Chemicals on the Body
Carcinogen a chemical that causes or potentially causes cancer (e.g. asbestos, formaldehyde)

Corrosive a chemical that causes visible destruction of or irreversible alterations in, living
tissue by chemical action at the site of contact (e.g. hydrochloric acid)
Irritant a chemical that is not corrosive, but that causes reversible inflammatory effects on
living tissue at the site of contact (e.g. strong solvents)
Mutagen a chemical that damages chromosomes (e.g. benzene)
Sensitiser a chemical that will cause an allergic reaction in a substantial number of exposed
people (e.g. isocyanates)
Teratogen a chemical that causes birth defects (e.g. thalidomide)
Some common examples of the effects of hazardous chemicals include:
■ Skin irritation, dermatitis or skin cancer from frequent contact with oils.
■ Injuries to hands and eyes from contact with corrosive liquids.
■ Asthma resulting from sensitisation to isocyanates in paints and adhesives.
■ Long-term disability from lung diseases following exposure to dusty environments (e.g.
exposure to respirable crystalline silicate).
■ Death or injury from exposure to toxic fumes (e.g. carbon monoxide).
■ Cancer causing death many years after first exposure to carcinogens at work (e.g. asbestos)
“The form in which these hazardous substances exist is important. For instance metals exist
as the native material (e.g. chromium metal) or as different salts (e.g. chromium oxide), and
the metal ion may exert different toxic effects depending on its form”.
“Some metals are toxicwhen they form poisonous solublecompounds.Certain metalshaveno
biological role, i.e. are notessentialminerals,or are toxic when in a certain form.In the caseof lead,
any measurableamountmay havenegativehealth effects.Often heavy metals arethoughtas
synonymous,butlightermetalsmay also be toxic in certain circumstances,such
as beryllium and lithium”

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