Many deaths and injuries arise from:

Handling of poorly tested or maintained equipment;

• working in close proximity to overhead power lines;

• contact with an underground power cable during groundworks;

• mains electricity supplies

• use of unsuitable equipment in an explosive area such as car paint spraying booth.

Simple Precautions

Electrical Safety/Warning SignFires started by poor electrical installations and faulty electrical appliances cause many additional deaths and injuries

There are some simple precautions that can be taken that will significantly reduce the risk of electrical injury to you and others around you:

• General work

• Work near electricity

• Work using electrically powered equipment

• Work on electrical equipment, machinery or installations

• Electricity in potentially explosive atmospheres

Electrical injuries

Electrical injuries can be caused by a wide range of voltages but the risk of injury is generally greater with higher voltages and is dependent upon individual circumstances.

Alternating current and Direct Current electrical supplies can cause a range of injuries including:

• Electric shock

• Electrical burns

• Loss of muscle control

• Thermal burns

Electric shock

A voltage as low as 50 volts applied between two parts of the human body causes a current to flow that can block the electrical signals between the brain and the muscles. This may have a number of effects including:

• Stopping the heart beating properly

• Preventing the person from breathing

• Causing muscle spasms

The exact effect is dependent upon a large number of things including the size of the voltage, which parts of the body are involved, how damp the person is, and the length of time the current flows.

Electric shocks from static electricity such as those experienced when getting out of a car or walking across a man-made carpet can be at more than 10,000 volts, but the current flows for such a short time that there is no dangerous effect on a person. However, static electricity can cause a fire or explosion where there is an explosive atmosphere.

Electrical burns

When an electrical current passes through the human body it heats the tissue along the length of the current flow. This can result in deep burns that often require major surgery and are permanently disabling. Burns are more common with higher voltages but may occur from domestic electricity supplies if the current flows for more than a few fractions of a second.

Loss of muscle control

People who receive an electric shock often get painful muscle spasms that can be strong enough to break bones or dislocate joints. This loss of muscle control often means the person cannot ‘let go’ or escape the electric shock. The person may fall if they are working at height or be thrown into nearby machinery and structures.

Thermal burns

Overloaded, faulty, or shorted electrical equipment can get very hot, and some electrical equipment gets hot in normal operation. Even low voltage batteries can get quite hot may overheat and explode if they are shorted out.

People can receive thermal burns if they get too near hot surfaces or if they are near an electrical explosion. Other injuries may result if the person pulls quickly away from hot surfaces whilst working at height or if they then accidentally touch nearby machinery.

A single low voltage torch battery can generate a spark powerful enough to cause a fire or explosion in an explosive atmosphere such as in a paint spray booth, near fuel tanks, in sumps, or many places where aerosols, vapours, mists, gases, or dusts exist.