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Electricity can be the cause of numerous kinds of accidents and fires within Churches and Places of Worship. Some serious accidents involving electricity can be fatal and fires can be started by faulty electrical equipment or wiring.
Electrical safety basics
A number of injuries can be sustained from an electric shock. Injury types could include serious burns, with internal burns being common and often undetected without medical treatment. The flow of current can stop the heart and affect breathing, or put the heart out of normal rhythm. The muscle spasms caused by the electric current could cause other, secondary injuries (for example a broken bone because of a fall from a ladder).
It is the current that does the harm, not the voltage, and a surprisingly small current flow (measured in fractions of one Amp) through the chest can stop the heart or lungs working properly.
Heat can be produced by overloaded sockets or wiring, through damaged electrical cabling or equipment or a loose connection. Some appliances give off heat, such as radiators and stage lighting, and these appliances can be a further cause of electricity-related fires if they are not used correctly. Electricity causes a significant number of avoidable fires in UK premises.
Portable appliances
The term 'portable appliance' can be used for many pieces of equipment that are fitted with a mains plug, not just those that are moved about.
Different mains plugs may be encountered:
- The standard UK 13-Amp plug and socket;
- Keyed 13-Amp plugs and sockets, which have special pin orientations or shapes to prevent the standard 13-Amp plug being inserted (ideal for places where the public might misuse a normal socket);
- Industrial CEE or Commando plugs, for heavy-current appliances and special uses. These are usually coloured yellow (110V), blue (230V) or red (400V, 3-phase);
- 5A and 15A round-pin, which are now considered obsolete for all but stage lighting systems or other special uses;
- IEC plugs, typically used with computer equipment and sound systems.
- Special plugs and sockets, for example those connecting organ consoles to control points around the Church.
In general, there are a two classifications of portable appliance used on the normal mains supply, Class I and Class II. Class I appliances usually have metal casing and must be connected to an earthed supply. Class II (also known as double insulated) have two layers of insulation to prevent a fault causing an electric shock. Class II appliances are marked with the 'Double Square' symbol and do not need earthing.
With all electrical equipment, follow the manufacturer's guidance and instructions and use the equipment only for its intended purpose.
Don't trail cables where they could be a trip hazard, near water or near equipment that gets hot and make sure that ventilation holes are kept free of obstruction. Ensure that nothing is placed on top of a mains cable that could deform or damage the insulation.
Inspection and Portable Appliance Test
The law requires that electrical installations and equipment are maintained in good working order. As part of this maintenance procedure, many people undertake Portable Appliance Testing (or PAT for short). Although not compulsory, it is highly recommended that PAT testing is undertaken, and many insurers will require this to be carried out.
PAT testing is often assumed to have to be done annually, but this depends on the appliance and where it is used. Some appliances do not need such frequent testing, while others might need more frequent testing depending on what the equipment is and where it is used. Some appliances need only a 'formal visual inspection' by a competent person while others require a series of electrical tests to check the integrity of the appliance.
In any case, if PAT testing is needed, it must be carried out by a competent person.
Each appliance is usually numbered and recorded in some form of log book or test record. A label is usually applied to the appliance or plug to show it has passed the test. Any failed appliances should be either repaired or disposed of, and the plug should be taken off so that the appliance cannot be used.
The majority of faults on electrical equipment are visual defects, such as a damaged flexible cord or incorrectly wired mains plug or a mains plug that does not have plastic 'sleeving' on the Live and Neutral pins. In some situations, a quick check might be needed to look for damage, the correct fuse and secure wiring.
In addition to a visual inspection, the Portable Appliance Test includes a series of electrical tests that ensures the electrical integrity of the appliance. This testing is performed using equipment designed specifically for testing portable appliances.
Appliances should be quickly checked for damage before each use. This need only be a very quick check of the plug, the appliance and the flexible cord
Extension Leads
Extension leads are often used to enable an appliance to be used some distance from a mains outlet but these should be avoided if possible. These extensions and cables should also undergo a Portable Appliance Test like any other piece of equipment.
Extensions should normally only be used for low-current equipment, so heaters, kettles and other cooking equipment should not usually be plugged in. Most extension reels need to be fully unwound, and many also include a special temperature trip that will cut out the power if the lead gets too hot.
Additional lengths of cable should not be added onto the flexible cord of appliances and, because of the risk of overloading sockets, do not use multi-socket adapters. Very long extension leads should be avoided.
A useful phrase to remember to prevent overloading is 'One socket - One Plug - One appliance'.
Fixed installation and wiring
The fixed installation includes all fixed electrical wiring within the building. It includes light switches, sockets, light fittings and the distribution boards or fuse boxes (which are usually situated near to the supply meter) along with all of the cabling.
It is common practice in many places of public assembly to keep parts of the electrical installation out of the reach of members of the public. This includes the fuse boxes and distribution boards, light switches and power sockets. This is especially important where industrial or non-standard power connectors are used and it also prevents the unauthorised use of equipment that has not been PAT tested or checked. Additionally, it prevents unauthorised use of electrical power and prevents people accidentally or maliciously turning off lights and power.
The most important part of any electrical installation is the 'earth' connection, which is used to ensure that metal items cannot become 'live'. It is common to have a number of items connected to the electrical earth, including pipes, large metal structural elements of the building and heating system parts alongside the other parts of the electrical installation.
Socket Covers
It is worthwhile noting that the British Standard 13 Amp socket has safety shutters which prevent objects being inserted into the live parts of the socket. As such, it is not necessary to use any further protection, such as plastic socket covers that are commonly available on the high-street. Many of these covers have actually been found to pose a greater hazard to children, and can damage the inner workings of the socket.
For more information about socket covers, please see the Fatally Flawed Website.
Fuses, Circuit Breakers and RCDs
The electrical installation includes a number of safety devices, including fuses and circuit breakers that are designed to turn off the power if a fault develops. A fuse or circuit breaker is designed to break the circuit should a fault develop, such as a short-circuit or overload.
Residual Current Devices (sometimes called 'RCD' for short) are a type of circuit breaker that reduces the chance of someone receiving a significant shock by detecting certain kinds of fault where a fault current 'leaks' to earth. This is essential for power used out of doors and in high-risk environments, such as in kitchens or near water.
Note, however, that an RCD is not a substitute for electrically-sound electrical installations or appliances. Where equipment is exposed to water, it must be adequately water-tight regardless of the use of an RCD.
It is recommended that RCDs are installed into the main distribution board, so it always provides protection to the power circuits. When this is not possible, individually protected sockets or adaptors can be provided or the plugs to appliances can be upgraded. Be aware that it is not advisable for a single RCD to protect the whole mains installation as a fault on a power circuit would also interrupt the supply to the lighting circuits. Today's standard is to use at least two RCDs that each protect a portion of the wiring.
Some installations might have voltage-operated Earth Leakage Circuit Breakers. These are now considered obsolete and should be replaced for Residual Current Devices.
Fixed wiring checks
Electrical wiring works should only be completed by a competent person, who will certify the works as complying with an industry standard (usually British Standard 7671, previously known as the IEE Wiring Regulations). The certificate is issued to show that the installation has passed a number of safety tests and is in a generally safe condition. Ideally, the certificate should be issued from a contractor registered with the National Inspection Council for Electrical Installation Contracting.
It is recommended that electrical installations should be inspected periodically for safety by a competent person. For some premises, this might need to be as much as every year, but for many premises, where the installation is in a good state of repair and the risk is lower, a five yearly inspection is common. The electrician performing the inspection and test will produce an inspection certificate and this needs to be kept for future reference.
Some simple checks can be routinely made on the electrical installation to ensure safety. This includes a visual inspection of socket outlets for damage or scorch marks and the operation of the test button on all RCDs. Any defects should be repaired as soon as possible.
Maintenance work
In order to maintain safety, and to improve the installation, work on the electrical wiring and other parts of the installation is sometimes needed. Always ensure that people working on electrical equipment and systems are competent to do the work. Professional electricians should be able to demonstrate their qualifications and experience, and show a copy of their insurance certificates on request.
Work on live electrical systems and equipment should be avoided, and specific safe systems of work should be in place to carry out the task needed. In the majority of situations, work needs to be completed with the electrical power isolated from the equipment or circuit being worked on and care must be taken to make sure power is not turned back on when someone is still working on the circuit. Circuits should be proven dead before work commences.
Lower voltages and batteries
A number of the risks associated with mains power can be removed if lower voltages are used. Most power tools used by contractors and maintenance personnel use 110 Volt (centre tapped earth) power for safety, and these are supplied from a special transformer, usually yellow in colour.
12- or 24- Volt power supplies are often used for equipment such as festive and decorative lighting or equipment that is being used out of doors or near water. These voltage supplies are known as 'Extra-Low Voltage'. Ideally, mains voltage festive lighting should not be used but instead transformer-fed sets used (ideally LED rather than incandescent lamps).
Similarly, battery equipment, especially tools, are usually considered to be much safer than mains powered equipment. Note that some kinds batteries, including car batteries and other high-capacity lead-acid types, are not recommended as these can produce quantities of flammable gas or allow significant current flow in the event of a short circuit.
Overhead and buried power lines
Overhead power lines or buried cables provide mains power to buildings. Sometimes electrical distribution equipment (such as power transformers), which is owned and operated by the local 'Distribution Network Operator', may be sited in the grounds of a Church or Place of Worship.
Overhead power lines are often not insulated, and contact with these could result in a serious electric shock. In some rural settings, high-voltage overhead lines might be encountered. It is not uncommon for voltages as high as 11000 volts to be used near local distribution equipment (higher voltages are used near larger substations and on some power lines that may be encountered).
Buried power lines can be struck while digging and care is needed to trace cables before starting any work. When in doubt, contact the local Distribution Network Operator and always check for live cables before digging or excavating.
Additional Information
Further guidance on electrical safety regulations is available in an HSE publication, "Memorandum of guidance on the electricity at work regulations 1989". Guidance Note GS50, "Electrical safety at places of entertainment" also provides some useful additional information about the use of sound and lighting systems etc...
A competent electrician should be contacted about fixed installation wiring (and appliances if there is any doubt). It is common practice to use British Standard BS7671 (also known as the IEE wiring regulations) as a guide for installations.
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