Few safety measures commonly used in industries comprise of the proper safety guards for reciprocating machine components such as drop hammers, presses, shaper, slotter, power hacksaw, paper cutters etc., fencing of dangerous and rotating parts like revolving shafts, incorporating safety devices such as safety valves, rigid construction of heavy items like hoists, cranes etc, proper insulation of electric wire and earthing of electric appliances, wearing appropriate safety shoe and other necessary items for, body protection, maintenance cleanliness of shop floor, removal of metal chips with proper protection, avoiding fire hazard. Safety while working safely in any shop is the safety of human being and the safety of workshop machinery. Hence there is a great need for the study of the domain of industrial safety for accidents prevention and good house keeping is the utmost. Safe working conditions in any industry may help to minimize the number of accidents taking place, prevent premature death of talented employee, prevent needless pain and suffering to industrial employees, reduce damages to equipment and machinery, increase production and reduce production cost. Good housekeeping implies keeping industry clean, look pleasant well illuminated and ventilated so that accidents are minimized, total production and quality are improved and the employee morale is boosted. Careless handling of heavy materials and components is a major source of back and foot injuries. To avoid premature fatigue of transport workers, full use should be made of mechanized materials handling equipment. Use mechanical means of conveyance to ensure the safety of men engaged in material handling. The transport workers should not be asked to lift more than the permissible load. Personal protective devices such as safe hard hats, rubberized hats for protection against liquids /chemicals, ear protectors, face mask/face shields, welding helmet, goggles of case-hardened and clear glass for protection against impact should be used as per the need.
The good housekeeping has been borrowed from the maintenance of domestic properties in the home or house and is now liberally applied to the maintenance of both cleanliness and order in all kinds of business establishments, e.g., industries etc. Cleanliness is a condition wherein buildings, work and rest areas, machinery, equipments and tools are kept free from dirt, dust etc. Necessity of good housekeeping is essential in order to make and maintain a clean and neat factory work in its surroundings. It makes work more pleasant, most satisfying and motivate for all kind of employees to work. The advantages of good house keeping are fewer accidents, increased life of building, machinery, tools, etc., improved employee morale, increased production, better product quality, continuous cleaning reduces housekeeping costs, no time is lost in searching for tools etc, material handling and transportation pick up speed, inspection, maintenance and production control functions become easier, much floor space otherwise occupied by unused raw material and tools. A good house keeping procedure involves plan and project the housekeeping program carefully and completely.
COMMON SAFTY METHODS
The common methods of safety are as follows:
1. Safety by construction or design.
2. Safety by position.
3. Safety by using fixed guards.
4. Safety by using interlock guards.
5. Safety by using automatic guards.
6. Safety by using trip guards.
7. Safety by using distance guards.
8. Safety by workplace layout and proper working conditions.
9. Safety by proper material handling.
10. Safety by using personal protective devices.
Few of the above methods of safety are discussed as under.
Safety by Construction
Whenever the new tools, devices, equipments and machine are designed, they should be ensured that all their dangerous parts are either enclosed in suitable housings or provided with suitably designed safety guards in order to eliminate any chances of danger that could occur due to exposure of the dangerous parts. A common example involve belt drive and motor in a in drilling machine, lathe, milling or in other machines are enclosed, the back gears and tumbler gears in a lathe are either enclosed or provided with cast iron guards or covers. All control levers and handles of machines should be carefully located to ensure adequate safety in their operation. Generally, lubricating points are provided on the outer surface that the interior parts are not required to be opened every now and then.
Safety by Position
The main principle involved in the method for safety by position is to design the machine in such a way that the dangerous parts are so located or placed that they are always beyond reach of the operator. It is therefore always advisable that all the dangerous parts of the machine should invariably be guarded or enclosed in the body or housing of the machines as far the design conditions permit. If it is not possible suitable external fencings must be incorporated suitably.
Safety by Using Fixed Guards
Such fixed guards either form an integral part of the machine or are so tightly secured to them that they are not easily removable. In all cases, fixed guards are developed to have a robust and rigid construction and they should be so placed that any access to the dangerous parts of the machine is totally prevented from all directions particularly in the running condition of the machines. Fixed guards adjusted in position remain fixed and they are neither moved nor detached. In some cases the fixed guards are provided at a distance from the danger point. Such a provision will carry a remote feeding arrangement and, therefore, the operator will not be required to go near the dangerous points.
Safety by Using Interlock Guards
An interlocking guard may be mechanical, electrical, pneumatic or some sort of a combination of these. Such guards cannot be removed and the dangerous parts are not exposed until and unless the machine is totally stopped. Similarly, the machine cannot be started to work unless the guards return in position and protects the dangerous parts. It is essential that such guards should always acquire their positions to guard the dangerous parts before the machine can be started,. Such arrangements prevent the starting and operation of the machine in case the interlocking device fails and remain closed in position until the dangerous part is completely at rest. Scotch interlocking and control interlocking designs of these guards are common used to protect accidents. The former interlocking consists of a solid metal piece, called scotch connected to it which is so located that it remains between two moving parts of the machine. This prevents the machine from starting so long as the same is not removed and the guard brought in proper position for protection. The latter comprises of the movable portion of the guard as connected to some starting device or mechanism of the machine viz., fast and loose pulleys, clutch, starter of the motor or tile hydraulic valve, etc. This connection is made in such a way that it will not allow the operation of the said device or mechanism until and unless the guard is brought in protecting position, which automatically enables its removal from that position from where it prevents the operation of the starting mechanism.
Safety by Using Automatic Guards
The main principle of an automatic guard is that its operation is actuated by some moving part of the machine. Automatic guard and machine operation is so linked that the part will automatically bring the guard in protecting position before the operation of the machine starts. The design of this guard is of such a kind that it automatically forces the operator to move away from the dangerous area of work before the operation starts. Such arrangement of such guard does not permit the operator access to this area again until and unless the machine stops. The use of such guard is largely favored for heavy and slow acting machines like heavy power presses.
Safety by Using Distance Guards
Distance guard helps to fence the dangerous components of machine such as bars or rails and position them at a suitable distance from the machine such that even operator by chance, extends his hands over it, his fingers, clothes or any of the body does not reach within the area of dangerous parts. For additional safety, some sort of tripping device should always be incorporated to stop the machine rapidly in case of an accident.
Safety by Using Trip Guards
Trip guard in machine is comprised with tripping device which enables quick stopping or reversal of the motion of machine as soon as the operator approaches within the reach of dangerous parts. Tripping device and the trip guard works in close conjunction with each other during problematic situations.
3.8.8 Safety by Workplace Layout and Proper Working Conditions Some safety using workplace layout and proper working conditions are given as under:
1. A suitable layout and proper working conditions play an important role in preventing accidents which would have otherwise occurred.
2. Moving path or passage ways should be clearly marked and never be obstructed.
3. Every employee should have enough space to move and operate the machine.
4. The floor condition must be of non-skid kind. It should act as a satisfactory plane which can be easily cleaned.
5. Height of working rooms should be adequate for proper ventilation and lighting.
6. Fire walls should be used to separate various compartments.
7. Windows should have adequate size and should be in adequate numbers.
8. Illumination should be sufficient, continuous, uniform and free from glare.
9. Proper ventilation should be there in workplace.
10. Noise level should be proper if any. If it is high, use silencers to minimize the noise level.
TYPES OF SAFETY
The fo1lowing general types of safety are considered in the workshop
1. Safety of self.
2. Safety of job.
3. Safety of machines tools.
However there are general safety precautions to be adopted while working in any workshop
General Safety Precautions while Working in a Workshop
1. One should not leave the machine ON even after the power is OFF and until it has stopped running completely. Someone else may not notice that the machine is still in motion and be injured.
2. Operator should not talk to other industrial persons when he is operating a machine.
3. One should not oil, clean, adjust or repair any machine while it is running. Stop the machine and lock the power switch in the OFF position.
4. One should not operate any machine unless authorized to do so by the authorize person in the shop.
5. Always check that work and cutting tools on any machine are clamped securely before starting.
6. The floor should be kept clean and clear of metal chips or curls and waste pieces. Put them in the container provided for such things. Scraps and chips or curls may cut through a shoe and injure the foot.
7. Defective guards must be replaced or repaired immediately.
8. One should not operate any machinery when the supervisor or instructor is not in the shop.
9. All set screws should be of flush or recessed type. Projecting set screws are very dangerous because they catch on sleeves or clothing.
10. One should not try to stop the machine with hands or body.
11. Only trained operator should operate machine or switches as far as possible.
12. Always take help for handling long or heavy pieces of material.
13. Always follow safe lifting practices
14. No one should run in the shop at work time.
15. Always keep your body and clothes away from moving machine parts. Get first aid immediately for any injury.
16. Never talk to anyone while operating the machine, nor allow anyone to come near you or the machine.
17. Stop the machine before making measurements or adjustments.
18. Operator should concentrate on the work and must not talk unnecessarily while operating the machines.
19. Never wear necktie, loose sweater, wristwatch, bangles, rings, and loose fitting clothing while working in workshop.
20. Always wear overcoat or apron.
21. Stop machines before attempting to clean it.
22. Make sure that all guards are in their place before starting to operate a machine.
23. Do not attempt to operate a machine until you have received operating instructions.
24. Be thoroughly familiar with the ‘stop’ button and any emergency stop buttons provided on the machines.
25. Remove burrs, chips and other unwanted materials as soon as possible. They can cause serious cuts.
26. Do not leave loose rags on machines.
27. Wash your hands thoroughly after working to remove oils, abrasive particles, cutting fluid, etc.
28. Report all injuries to the foreman, howsoever small. Cuts and burns should be treated immediately.
29. Keep the work area clean.
30. Keep your mind on the job, be alert, and be ready for any emergency.
31. Always work in proper lighting.
32. On should not lean against the machines.
Safety Precautions while Working with Different Hand Tools
(A) Screw Drivers
1. When working on electrical equipment use only a screw driver with an approved handle.
2. One should wear goggles when re-sharpening screw-driver tips.
3. Screws with burred heads are dangerous and must be replaced or the burrs removed with file or an abrasive cloth.
4. One should use the correct tip of screw drivers while screwing. Too arrow or too wide tip will damage the work.
1. One should not hammer a wrench to loosen a stubborn fastener, unless the tool has been specially designed for such treatment.
2. Always pull on a wrench. One can have more control over the tool if pulling instead of pushing and there is less chance of injury.
3. It is dangerous practice to lengthen the wrench handle for, additional leverage. Use a larger wrench.
4. Choose a wrench that fit properly. A loose fitting wrench may slip and round off the corners of the bolt head and nut.
5. When using wrenches clean grease or oil from the floor in the work area. This will reduce the possibility of slipping and losing balance.
1. One should not operate the hammer unless its head is tightly fixed to the handle.
2. Place the hammer on the bench carefully. A falling hammer can cause serious foot injuries.
3. Never strike two hammers together. The faces are very hard and the blow might cause a chip to break off.
4. Never hold the hammer too far on the handle when striking a blow.
5. Unless the blow is struck squarely, the hammer may glance of the work.
Safety Precautions while Working with Different Cutting Tools
1. One should always use a file card to clean the file. Never use your hand. The chips may penetrate in hand and cause a painful infection.
2. One should not use a file without a handle.
3. Short burns formed in filling may cause serious cuts. Always use a piece of cloth to wipe the surface being field.
4. Files are highly brittle and should never be used as a hammer otherwise the file will break.
5. Never hammer on a file. It may shatter and chips fly in all directions.
1. One should always hold the chisel in such a manner that the hammer blow may not miss the chisel to injure your hand.
2. Edges of metal cut with the chisel are often sharp and cause bad cuts.
3. Flying chips are dangerous. Wear transparent plastic safety goggles and use a shield, when using a chisel, to protect yourself and those working near you.
4. Sharp edges of chisels are removed by grinding or filing.
5. Mushroomed head of the chisel should be removed by grinding.
1. One should not test the sharpness of the blade by a running a finger across the teeth.
2. One should not brush away the chips with your hand.
3. All hard blades can shatter and produce flying chips. Wear your toggles.
4. One should not be sure that the blade is properly tensioned.
5. Store the saw so that you will not accidentally reach into the teeth when you pick it up.
6. If the blade breaks while you are on cutting stroke, your hand may strike the works and cause an injury. Therefore saw operator should work carefully.
1. One should remove all bars from the reamed holes.
2. Never use your hands to remove chips and cutting fluids from the reamer and work. One should use a piece of cotton waste.
(E) Taps and Dies
1. One should use a brush to clean away chips formed by hand threading. Never use your hand.
2. One should always wear goggles if the tap, die or threaded piece is to be cleaned with compressed air.
3. Tap operator should also be careful that other person working in the area also wearing goggles.
4. Handle broken taps as you would handle broken glass. They are sharp edges and are dangerous to handle.
5. Wash you hands after using cutting fluid. Skin-rashes caused by some cutting fluids can develop into a serious skin disorder if they are left on the skin for a long period.
6. Take care of any cuts immediately. Infection may occur when injuries are not properly treated.
1. If the lathe is used for polishing make sure that the machine is protected from the abrasive grains that fall from the polishing wheels during polishing. They can cause rapid wear of the precision parts.
2. One should not rub fingers or hand across a piece that has just been polished by abrasive.
3. Cuts and burns should always be treated immediately by using first aid facility.
4. One should remove all abrasive particles by washing them thoroughly after the polishing operation.