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Risks of Electricity
Accidents involving Electricity
Electricity can cause accidents and fires. If an accident is caused by contact with electricity, switch off the current immediately. Failure to do so can result in death. Electricity can kill and should be dealt with by electricians; do not attempt to deal with power cable problems.
Accidents can occur when people touch part of a unit carrying live current. Even contact with part of a unit which does not normally carry live current can lead to serious accidents if the insulation becomes faulty. Where electric arcs are formed, there is a high risk of burning and damage to eyesight.
There are two forms of accidents caused by electricity :
- Accidents due to direct contact with electricity
- Accidents caused by the formation of an electric arc.
Accidents involving electricity are often caused by failing to ensure that the safety system is working or by failing to follow the established safety rules. All electric installations should be serviced only by qualified electricians.
Electric current can also cause burns. If the insulation is faulty and there is a short-circuit, intense heat can develop, leading to the possibility of a serious fire. A common cause of fatal accidents is the attachment of electric cables to gas tubes.
If the short circuiting occur in or near a container with a highly explosive mixture of gas and air, the results could be very dangerous. Using spirits to clean an electric motor, and then starting it up immediately after cleaning can also cause an explosion or fire.
Wires and cables should not be hung over structural elements such as nails or other metal hooks, as these can wear through the insulating cover around the wires and cables. Dragging and coiling cables and wires can also damage the insulating covering.
Hand lamps
Hand lamps are among the most dangerous portable appliances in any workplace. Wherever possible, their use should be limited and they should be replaced by permanent lamps. It is also very important that the lamps used are of an approved design and that they are of the best quality. An electric hand lamp should have a framework and a hand grip made of insulating material, and have a protective basket around the bulb. Hand lamps easily become worn and should be checked regularly to ensure that they are safe.
Power-driven machines
The only way to avoid accidents due to electricity when working with power-driven machines is to ensure that the machines are properly constructed and maintained in good working order. Those parts which carry current should be properly insulated. Elements such as control handles and driving wheels should be made of insulating material.
An emergency stop device must be located within the operator’s reach. It may also need to be reached by other people. This is the case with emergency stop buttons fitted to excavators, conveyor belts or automated production lines. Emergency stop devices normally immobilize all functions on a machine immediately. However, they must not cause dangerous movements such as putting electronic brakes out of action. Electrical machine installations should also be equipped with relays that trip when the current is too low or when there is a power cut. The relay must be reset before the machine can be restarted when the current has reached its normal level.
Elements such as motor frames and protective hoods should be earthed. Those who work on fixed electrical machines should stand on insulating material.
Wires and cables to machines should be fixed to the wall. Loose cables should be avoided. If it is used, it should only be used for appliances like hand lamps. Never use contacts which have not been properly approved and avoid sticking bare wires into contacts or similar dangerous make-shift connections.
Power-driven hand tools
For power-driven hand tools use the following tips:
Workers with improper training in the use of power-driven tools should not be allowed to use them.
Always avoid working with live cables.
Use a voltage tester to check that the cables are not live.
Insulate yourself from live cables by using insulated tools and rubber gloves and footwear.
Cover any live cables in the area with insulating material, for example special plastic covers.
Power-driven hand tools frequently replace conventional hand tools. Since they involve greater accident risks, greater demands are made on the worker using them. Power-driven tools should be fitted with a safety earth.