Electrical Hazards

There were about one thousand reported electrical accidents that occurred within the workplace in the UK of these 25 were fatal.  Mains electricity, high voltage cables, batteries, static and even lightning can be found or occur in the workplace.  The HSE reports show that the most common injuries and deaths come from direct contact with an electrical charge and can be a direct result of badly maintained equipment, especially portable electrical equipment.

Other hazards include:

• Items or machines coming into contact with overhead power lines
• The use of unsuitable electrical equipment in wet areas or areas where there is the risk of explosion
• Working with live mains power
• When the body comes into contact with underground power lines while using hand tools or machinery.

When a body part comes in to contact with or close to a live source of electricity the body becomes the link from live to earth and the electricity transfers through the body to earth.  The body will convulse as the electricity passes through the muscles. A current as little as 10 milliamps will cause muscle contraction which can cause the hands, for example, to close around the source of the electricity so that the person cannot release it.  

The amount of damage or injury caused will depend on the size of the current passing through the body and the length of time that the person was in contact with the current. Also, the path of the electricity made through the body will affect what injury occurs.  A current of as little of 60mA can be fatal if the conditions are wet because this reduces the bodies resistance and can affect the hearts electrical activity causing a cardiac arrest.

Burns are also a problem as the electricity enters the body but also as it exits the body. These burns can be very severe as the electricity penetrates deep into the body these burns can be very painful and slow to heal.   Electricity can also cause sparks and this can result in fire or explosion.  Portable electrical equipment is of particularly high risk due to a high level of wear and tear as a result of being moved. Items such as plugs, wires and where the wire joins the appliance can get damaged and result in damage exposing bare wires.

Mains equipment is not the only electrical equipment that can cause serious injury, the HSE figures show that about 25 people a year are seriously injured by batteries.  Batteries can be single-use or rechargeable and they can be sealed or contain harmful chemicals and acids. They can potentially explode after the terminals have been short-circuited.  

Some of the injuries caused by batteries include:

• Electrocution from high voltage battery packs
• Exposure to the chemicals in the batteries
• Hydrogen and Oxygen are usually produced inside the battery and this can cause an explosion.

For more information on using stored electricity safely, the HSE have a publication INDG139 which we have put a link to on your student download area. Precautions you can take are to wear gloves and suitable eye protection, aprons and suitable boots in case of chemical spills.   Make sure no metal objects fall and short circuit the terminals and keep ignition sources away from batteries and keep the area well ventilated.

Fixed electrical equipment should be tested every 5 years or sooner when the risk assessment identifies the need. Portable equipment should be tested regularly according to the risk assessment and checked by users when they are used and any problems be reported and the equipment should not be used.  The testing of electrical work equipment covers new equipment as well as second hand and includes machinery, appliances, tools and installations. Activities include repair, modifications, servicing and cleaning.

Employees have the responsibility to report any faults, use equipment responsibly uses the equipment for the purpose it was designed and not to use faulty equipment.  Employers must ensure that equipment is suitable for the job; installed and located in a safe area and that the equipment is used correctly, used for the purpose provided and they should carry out a risk assessment for its use including ergonomic and environmental tasks.

Equipment must be well maintained and in an effective state of working order and the risk assessments should show the frequency of checks and maintenance carried out.  Finally, all electrical maintenance and the use of electrical equipment must be by a competent person and recorded.