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INDUSTRIAL SAFETY
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UNIT I

INDUSTRIAL SAFETY

DEFINITION OF ACCIDENT: An accident is a mishap or disaster that results in some sort of injury to man, machine, equipment or tools and hence causing loss of manpower, time and money to the establishment.

TYPES OF ACCIDENTS: Accidents may be classified according to their seriousness:

        Near accident or almost an accident but controlled in time to prevent any damage.

        Trivial or accident of little or almost negligible damage.

        Minor accident, where no major injury or damage to equipment has taken place.

        Serious accident, where serious injury resulting in loss of limb/s and/or major damage to workplace and equipment has taken place.

        Fatal accident, where there is loss of life/lives due to seriousness of accident.

NEED FOR SAFETY:

Accidents result in pain, loss of limbs or life, loss in terms of money and time, damage to workplace, equipment, tools and raw or finished materials.

It is therefore of utmost importance to practice safety rules and install safeguards at critical places. Also of importance is to train all personnel to practice and follow safety instructions at all times. Understand the need for safety and practice till it becomes a habit.

CAUSES OF ACCIDENTS IN INDUSTRY: Accidents don’t happen; they are caused either due to human error or negligence. It is not necessary that the error or negligence may have been caused by the directly involved persons but can also be on the part of people who are involved in policy decisions, purchases or quality assurance. Broad classifications of causes are as given below:

  1. UNGUARDED MOVING OR SHARP PARTS OF A MACHINE: Unprotected moving parts like chucks, flywheels, fan blades, gears, belts, grinding wheels etc. or sharp edges of blades, dies etc can cause accidents.
  2. EXPLOSIVE AND INFLAMMABLE MATERIAL: All petroleum products, inflammable gases and chemicals can cause serious damage if not handled or stored carefully.
  3. DEFECTIVE ELECTRICAL EQUIPMENT: Defective switches, plugs, sockets, safety breakers, wires and cables. Electrical equipment not properly earthed and faulty wiring can cause serious damage to life and equipment and is main cause of fire accidents.
  4. DEFECTIVE TOOLS AND IMPROPER USE : Trying to use a drill machine with faulty chuck, or using a lathe whose tool holder is loose or damaged. Trying to make and use unsafe tackle or use a tool for a purpose for which it is not designed. Such practices are usual cause of accidents taking place every day in workshops and small scale industry.
  5. FATIGUE : A tired person can loose focus and can commit mistakes. If the person is operating and equipment, he/she can cause accident.
  6. USE OF EQUIPMENT BY UNTRAINED WORKER : Another major cause of majority of accidents is the intentional or unintentional operation of equipment by personnel not supposed to operate them. This can cause serious damage to man and machine.
  7. UNSAFE WORKING CONDITIONS : Congested work place, slippery floors, improper ventilation, open and loosely hanging electrical wires, improper lighting, unbearable working temperatures. Such conditions also cause accidents.

All the above mentioned probable conditions are violation of safety norms as laid in INDUSTRIAL SAFETY ACT 1948. This act has been revised many times since then to take care of changes and development in manufacturing practices and technologies. But it still needs to be upgraded to include software industry.

 

PREVENTION : INDUSTRIAL SAFETY ACT 1948 is a complete document in itself and if all the provisions of this acts are followed diligently, the chances of accidents occurring will reduce drastically. The highlights of the safety provisions under this act are given below:

1. Fencing of machinery

(1) In every factory the following, namely:

(i) every moving part of a prime mover and every flywheel connected to a prime mover, whether the prime mover or flywheel is in the engine house or not;

(ii) the headrace and tailrace of every water-wheel and water turbine;

(iii) any part of a stock-bar which projects beyond the head stock of a lathe; and

(iv) unless they are in such position or of such construction as to be safe to every person employed in the factory as they would be if they were securely fenced, the following, namely,-

(a) every part of an electric generator, a motor or rotary converter;

(b) every part of transmission machinery; and

(c) every dangerous part of any other machinery;

shall be securely fenced by safeguards of substantial construction which shall be constantly maintained and kept in position while the parts of machinery they are fencing are in motion or in use:

2. Work on or near machinery in motion

while the machinery is in motion, such examination or operation shall be made or carried out only by a specially trained adult worker wearing tight fitting clothing (which shall be supplied by the occupier) whose name has been recorded in the register prescribed in this behalf and who has been furnished with a certificate of this appointment, and while he is so engaged-

(a) such worker shall not handle a belt at a moving pulley unless-

(i) the belt is not more than fifteen centimeters in width;

(ii) the pulley is normally for the purpose of drive and not merely a fly-wheel or balance wheel (in which case a belt is not permissible);

(iii) the belt joint is either laced or flush with the belt;

(iv) the belt, including the joint and the pulley rim, are in good repair;

(v) there is reasonable clearance between the pulley and any fixed plant or structure;

(vi) secure foothold and, where necessary, secure handhold, are provided for the operator; and

(vii) any ladder in use for carrying out any examination or operation aforesaid is securely fixed or lashed or is firmly held by a second person.]

No young person shall be allowed to clean, lubricate or adjust any part of a prime mover or of any transmission machinery while the prime mover or transmission machinery is in motion, or to clean, lubricate or adjust any part of any machine if the cleaning, lubrication or adjustment thereof would expose young person to risk of injury from any moving part either of that machine or of any adjacent machinery.

3. Employment of young persons on dangerous machines

(1) No young person shall be required or allowed to work at any machine to which this section applies, unless he has been fully instructed as to the dangers arising in connection with the machine and the precautions to be observed and-

(a) has received sufficient training in work at the machine, or

(b) is under adequate supervision by a person who has a through knowledge and experience of the machine.

4. Striking gear and devices for cutting off power

(1) In every factory-

(a) suitable striking gear or other efficient mechanical appliance shall be provided and maintained and used to move driving belts to and from fast and loose pulleys which form part of the transmission machinery, and such gear or appliances shall be so constructed, placed and maintained as to prevent the belt from creeping back on to the fast pulley;

(b) driving belts when not in use shall not be allowed to rest or ride upon shafting in motion.

(2) In every factory suitable devices for cutting off power in emergencies from running machinery shall be provided and maintained in every workroom:

5. Self-acting machines

No traversing part of a self-acting machine in any factory and no material carried thereon shall, if the space over which it runs is a space over which any person is liable to pass, whether in the course of his employment or otherwise, be allowed to run on its outward or inward traverse within a distance of [forty-five centimeters] from any fixed structure which is not part of the machine:

6. Casing of new machinery

(1) In all machinery driven by power and installed in any factory after the commencement of this Act,-

(a) every set screw, bolt or key on any revolving shaft, spindle, wheel or pinion shall be so sunk, encased or otherwise effectively guarded as to prevent danger;

(b) all spur, worm and other toothed or friction gearing which does not require frequent adjustment while in motion shall be completely encased, unless it is so situated as to be as safe as it would be if it were completely encased.

7. Prohibition of employment of children near cotton-openers

No child shall be employed in any part of a factory for pressing cotton in which a cotton opener is at work:

8. Hoists and lifts

(1) In every factory-

(a) every hoist and lift shall be-

(i) of good mechanical construction, sound material and adequate strength;

(ii) properly maintained, and shall be thoroughly examined by a competent person at least once in every period of six months and a register shall be kept containing the prescribed particulars of every such examination;

(b) every hoistway and liftway shall be sufficiently protected by an enclosure fitted with gates, and the hoist or lift and every such enclosure shall be so constructed as to prevent any person or thing from being trapped between any part of the hoist or lift and any fixed structure or moving part;

(c) the maximum safe working load shall be plainly marked on every hoist or lift, and no load greater than such load shall be carried thereon;

(d) the cage of every hoist or lift used for carrying persons shall be fitted with a gate on each side from which access is afforded to a landing;

(e) every gate referred to in clause (b) or clause (d) shall be fitted with interlocking or other efficient device to secure that the gate cannot be opened except when the cage is at the landing and that the cage cannot be moved unless the gate is closed.

(2) The following additional requirements shall apply to hoists and lifts used for carrying persons and installed or reconstructed in a factory after the commencement of this Act, namely:

(a) where the cage is supported by rope or chain, there shall be at least two ropes or chains separately connected with the cage and balance weight, and each rope or chain with its attachments shall be capable of carrying the whole weight of the cage together with its maximum load;

(b) efficient devices shall be provided and maintained capable of supporting the cage together with its maximum load in the event of breakage of the ropes, chains or attachments;

(c) an efficient automatic device shall be provided and maintained to prevent the cage from over-running.

9. Lifting machines, chains, ropes and lifting tackles

(1) In any factory the following provisions shall be complied with in respect of every lifting machine (other than a hoist and lift) and every chain, rope and lifting tackle for the purpose of raising or lowering persons, goods or materials:

(a) all parts, including the working gear, whether fixed or movable, of every lifting machine and every chain, rope or lifting tackle shall be-

(i) of good construction, sound material and adequate strength and free from defects;

(ii) properly maintained; and (iii) thoroughly examined by a competent person at least once in every period of twelve months.

(b) no lifting machine and no chain, rope or lifting tackle shall, except for the purpose of test, be loaded beyond the safe working load which shall be plainly marked thereon together with an identification mark and duly entered in the prescribed register; and where this is not practicable, a table showing the safe working loads of every kind and size of lifting machine or, chain, rope or lifting tackle in use shall be displayed in prominent positions on the premises;

(c) while any person is employed or working on or near the wheel track of a traveling crane in any place where he would be liable to be struck by the crane, effective measures shall be taken to ensure that the crane does not approach within six meters of that place.

(3) For the purposes of this section a lifting machine or a chain, rope or lifting tackle shall be deemed to have been thoroughly examined if a visual examination supplemented, if necessary, by other means and by the dismantling of parts of the gear, has been carried out as carefully as the conditions permit in order to arrive at a reliable conclusion as to the safety of the parts examined.

10. Revolving machinery

(1) In every factory in which the process of grinding is carried on there shall be permanently affixed to or placed near each machine in use a notice indicating the maximum safe working peripheral speed of every grindstone or abrasive wheel, the speed of the shaft or spindle upon which the wheel is mounted, and the diameter of the pulley upon such shaft or spindle necessary to secure such safe working peripheral speed.

(2) The speeds indicated in notices shall not be exceeded.

(3) Effective measures shall be taken in every factory to ensure that the safe working peripheral speed of every revolving vessel, cage, basket, fly-wheel, pulley, disc or similar appliance driven by power is not exceeded.

11. Pressure plant

(1) If in any factory, any plant or machinery or any part thereof is operated at a pressure above atmospheric pressure, effective measures shall be taken to ensure that the safe working pressure of such plant or machinery or part is not exceeded.

12. Floors, stairs and means of access

(a) all floors, steps, stairs, passages and gangways shall be of sound construction and properly maintained and shall be kept free from obstructions and substances likely to cause persons to slip], and where it is necessary to ensure safety, steps, stairs, passages, and gangways shall be provided with substantial handrails;

(b) there shall, so far as is reasonably practicable, be provided and maintained safe means of access to every place at which any person is at any time required to work.

(c) When any person has to work at a height from where he is likely to fall, provision shall be made, so far as is reasonably practicable, by fencing or otherwise, to ensure the safety of the person so working.

13. Pits, sumps, opening in floors, etc.

(1) In every factory every fixed vessel, sump, tank, pit or opening in the ground or in a floor which by reason of its depth, situation, construction or contents, is or may be a source of danger, shall be either securely covered or securely fenced.

14. Excessive weights

(1) No person shall be employed in any factory to lift, carry or move any load so heavy as to be likely to cause him injury.

15. Protection of eyes

In respect of any such manufacturing process carried on in any factory as may be prescribed, being a process which involves-

(a) risk of injury to the eyes from particles or fragments thrown off in the course of the process, or

(b) risk to the eyes by reason of exposure to excessive light.

16. Precautions against dangerous fumes, gases, etc.

(1) No person shall be required or allowed to enter any chamber, tank, vat, pit, pipe, flue or other confined space in any factory in which any gas, fume, vapour or dust is likely to be present to such an extent as to involve risk to persons being overcome thereby, unless it is provided with a manhole of adequate size or other effective means of egress.

(2) No person shall be required or allowed to enter any confined space as is referred to in sub-section (1), until all practicable measures have been taken to remove any gas, fume, vapour or dust, which may be present so as to bring its level within the permissible limits and to prevent any ingress of such gas, fume, vapour or dust and unless-

(a) a certificate in writing has been given by a competent person, based on a test carried out by himself that the space is reasonably free from dangerous gas, fume, vapour or dust; or

(b) such person is wearing suitable breathing apparatus and a belt securely attached to a rope the free end of which is held by a person outside the confined space.

16A. Precautions regarding the use of portable electric light

(a) no portable electric light or any other electric appliance of voltage exceeding twenty-four volts shall be permitted for use inside any chamber, tank, vat, pit, pipe, flue or other confined space, unless adequate safety devices are provided; and

(b) if any inflammable gas, fume or dust is likely to be present in such chamber, tank, vat, pit, pipe, flue or other confined space no lamp or light other than that of flame-proof construction shall be permitted to be used therein.

17. Explosive or inflammable dust, gas, etc.

(1) Where in any factory any manufacturing process produces dust, gas, fume or vapour of such character and to such extent as to be likely to explode to ignition, all practicable measures shall be taken to prevent any such explosion by-

(a) effective enclosure of the plant or machinery used in the process;

(b) removal or prevention of the accumulation of such dust, gas, fume or vapour;

(c) exclusion or effective enclosure of all possible sources of ignition.

(2) Where in any factory the plant or machinery used in a process such as is referred to in sub-section (1) is not so constructed as to withstand the probable pressure which such an explosion as aforesaid would produce, all practicable measures shall be taken to restrict the spread and effects of the explosion by the provisions in the plant or machinery of chokes, baffles, vents or other effective appliances.

(3) Where any part of the plant or machinery in a factory contains any explosive or inflammable gas or vapour under pressure greater than atmospheric pressure, that part shall not be opened except in accordance with the following provisions, namely:

(a) before the fastening of any joint of any pipe connected with the part or the fastening of the cover of any opening into the part is loosened, any flow of the gas or vapour into the part of any such pipe shall be effectively stopped by a stop-valve or other means;

(b) before any such fastening as aforesaid is removed, all practicable measures shall be taken to reduce the pressure of the gas or vapour in the part or pipe to atmospheric pressure;

(c) where any such fastening as aforesaid has been loosened or removed effective measures shall be taken to prevent any explosive or inflammable gas or vapour from entering the part of pipe until the fastening has been secured, or, as the case may be, securely replaced:

(4) No plant, tank or vessel which contains or has contained any explosive or inflammable substance shall be subjected in any factory to any welding, brazing, soldering or cutting operation which involves the application of heat unless adequate measures have first been taken to remove such substance and any fumes arising there from or to render such substance and fumes non-explosive or non-inflammable, and no such substance shall be allowed to enter such plant, tank or vessel after any such operation until the metal has cooled sufficiently to prevent any risk of igniting the substance.

18. Precautions in case of fire

(1) In every factory, all practicable measures shall be taken to prevent outbreak of fire and its spread, both internally and externally, and to provide and maintain-

(a) safe means of escape for all persons in the event of a fire, and

(b) the necessary equipment and facilities for extinguishing fire.

(2) Effective measures shall be taken to ensure that in every factory all the workers are familiar with the means of escape in case of fire and have been adequately trained in the routine to be followed in such cases.

 

PROTECTION AGAINST FIRE : Fire hazards can be caused due to various reasons. Different kinds of materials that cause fire hazard are to be dealt differently. For example, an electrical fault that causes fire is to be dealt with different kind of fire fighting material than the fire caught by wood or paper. Therefore fires are classified in three categories:

  • Class A fire: Fires in ordinary combustible materials like wood, paper, cloth etc are classified as ‘A’ class fire. This fire can be most effectively dealt with water. Fire extinguishers that are water based such as water CO2 and Soda acid types of fire extinguishers are also very effective.
  • Class B fire: Fires of inflammable materials like petroleum products such as petrol, diesel, kerosene, LPG, paints, solvents, greases, varnish etc. are classified in this category. These fires generated very high temperatures and if water is used on such fires it decomposes at such high temperatures and instead of extinguishing it, it inflames it. Therefore, sand or extinguishers that are foam type, carbon dioxide type or dry powder type should only be used.
  • Class C fire: Fires in electrical circuits, equipments and panels are called ‘C’ type fires. Water being a conductor of electricity, should never be used to extinguish class ‘C’ fires. Water based extinguishers such as water CO2 type should also not be used. Dry powder type extinguishers are most ideal for such fires. In fact, dry powder type extinguishers have gained popularity over the years and are now termed as universal type extinguishers and can be easily and effectively used on any type of fire. Other class ‘C’ type extinguishers are vapour liquid type & carbon dioxide type.

 

Storage houses and offices which are not manned 24 hours should be fitted with automatic sprinkler system. In this system water is stored at high pressure in pipes. The pressure is maintained by pumps at one end of the piping system and on the other end, which is inside office or store house complex, sprinklers are fitted. The opening of these sprinklers is blocked by capsules filled with volatile liquid. When temperatures inside these complexes rise beyond permissible limits due to fire, this volatile liquid expand and break the glass capsules. The opening is then free and water is sprinkled at high pressure in the high temperature zone, extinguishing fire.

 

Care should be taken while installing this system in warehouses where petroleum products are stored. There, sprinklers should be backed by powdered chemicals instead of water.

Water hydrant systems should be installed in buildings which are having four or more floors.

Fire alarm systems should be installed. Alarm systems sense change in temperature due to fire and activate audio alarms so that security personnel can immediately take suitable action.

All personnel working in a premise should be trained to use fire extinguishers. Drills should be conducted to train people how to react and vacate premises in case of fire. This training should be imparted by trained people.

Places of large gathering such as cinema halls, auditoriums, stadiums, multistoried buildings normally using electrically operated lifts or escalators, etc. should have emergency exits and stairs. These should be clearly marked and passages leading to them should also be marked so. There should be battery supported lighting backup to all such exits so that if electricity is switched off to prevent spreading of fire, these exits are well illuminated. All the doors for exit should open outward to avoid accidental locking in.

 

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