A stage and a row of catering units in a field have one thing in common. Neither came with a socket. Everything that makes an event work in a space like that runs off a temporary electrical installation for events, built on site by people who leave before the audience arrives and taken apart again afterwards.
In short
- A temporary system is a system in law from the moment it is switched on, so the duty does not wait for the paperwork to catch up.
- Somebody has to own the whole installation rather than each piece of it, and where the supply chain is split, often nobody does.
- Ask for the record of inspection and test before the audience is admitted, not after the event.
What a temporary electrical installation for events actually is
It is an electrical system built to run for the length of one job and then removed. There is a British Standard written for exactly this: BS 7909:2023, temporary electrical systems for entertainment and related purposes, published in January 2023, covering the design and operation of temporary low voltage systems. Low voltage here means the ordinary 230 and 400 volt supplies, not anything higher. Its own list of intended readers includes event organisers and managers, not only electrical contractors and hire companies.
Underneath the standard sits the law. Regulation 4 of the Electricity at Work Regulations 1989 says that all systems shall at all times be of such construction as to prevent, so far as is reasonably practicable, danger. The phrase doing the work there is “at all times”. The duty applies while a system is half built and a crew is still pulling cable, not from the moment somebody signs a sheet at the end.
Nobody is named as owning the whole system
A common arrangement on an open site is a generator from one company, distribution from another, and audio visual (AV) equipment from a third. Each of those firms is competent at its own piece. The installation is the sum of the pieces, and the sum has no owner unless somebody is named as owning it.
One supplier beats three here more clearly than anywhere else on an event, because an electrical system is one continuous thing. Where the joins cannot be removed, settle early who holds the design of the whole installation and who is told when anyone alters it. Your own duties as the organiser sit underneath all of it, and they are set out in who is actually responsible for health and safety at your event.
An earth has to be provided, not assumed
In a building the earth arrives with the supply and it is easy not to think about. A generator standing on grass has no earth at all until somebody makes one. Regulation 8 of the same Regulations requires precautions, by earthing or by other suitable means, to stop danger arising when metalwork that is not part of a circuit becomes live through a fault, and it treats a conductor as earthed only once it is connected to the general mass of earth by conductors strong enough to carry that fault.
Protective devices work by giving a fault somewhere to go. Without that connection, metalwork can sit live while nothing sees anything wrong. So ask who is providing the earthing arrangement on your site and who verified it.
Outdoors, the residual current device question is not a judgement call
A residual current device (RCD) cuts the supply when it detects current leaking out of a circuit. The Health and Safety Executive (HSE) is plain about the specification: an RCD should have a tripping current of not more than 30 milliamps, and it should never be bypassed.
BS 7671, the UK wiring regulations, calls for 30 milliamp additional protection on socket outlets of 32 amps or less. For ordinary locations there is a way out of that: a documented risk assessment, done with a skilled person, can conclude the protection is not needed. The Institution of Engineering and Technology’s own explainer makes clear that this way out does not extend to portable equipment used outdoors. On an open site it is not a decision anyone gets to make.
The same article makes a second point. Fitting these devices indiscriminately produces unwanted tripping. If a stage and a catering run both sit behind one device, a fault in a fryer takes the stage with it. Ask how the installation is divided and what stays up when something goes.
The parts that get taped instead of replaced
The HSE is specific about cables, and it is the line to put to anyone who arrives with a roll of tape. Check the cable is not damaged and has not been repaired with insulating tape or an unsuitable connector, and where it is damaged, replace it with a new cable, done by a competent person.
Damp changes the answers. The HSE says that in a damp environment you may choose battery or air powered equipment, or equipment running at a reduced voltage through a transformer centre tapped to earth, which halves the voltage between a live wire and earth.
Where cable crosses ground people walk on, it becomes part of the surface rather than something lying on it, which is covered in our piece on ground conditions for outdoor events. A walking route with lighting along its whole length, as in planning a Christmas light trail, is the extreme version of the same problem.
The document that says it was tested
The commercial set, the paperwork to ask a supplier for before the get-in, tells you about the company. The record of inspection and test tells you about the installation standing in your field.
Ask who designed the system, who built it, and what the test results were. Then ask whether, when a distribution run was added on the day, the record was updated to match what is actually plugged in. An installation that has been changed since it was tested is not the installation anybody signed for.
Frequently asked questions
Do we need a temporary installation if the venue already has sockets?
It depends how far past those sockets you go. Using what the venue provides, with its own maintenance behind it, is the venue’s installation. The moment you run distribution out to a marquee or a catering line, you have built something new on top of it, and that new part needs designing and testing by someone competent to do it.
What does a 30 milliamp RCD actually do for us?
It cuts the supply when it detects current leaking out of a circuit, which is what happens when someone becomes part of that circuit. The Health and Safety Executive is careful about how much credit to give it: one of these devices can reduce the likelihood of an electrical injury, but a shock can still cause very serious or fatal injuries. It lowers the odds without removing them.
Sources
- legislation.gov.uk · Electricity at Work Regulations 1989, regulations 4 and 8
- British Standards Institution · BS 7909:2023, temporary electrical systems for entertainment and related purposes
- Health and Safety Executive · Work using electrically powered equipment
- Institution of Engineering and Technology · Wiring Matters on 30 milliamp protection for socket outlets
If you have an event going into a space with no power of its own, or an outdoor stage that needs a supply built for it, we are happy to look at the whole system rather than one part of it. We deliver nationwide from Manchester, so tell us what the site is and what has to run on the night, and we will tell you what it needs and who has to sign for it. You can reach us through the contact page or by email at hire@eventproductiongroup.co.uk, and if a straightforward supply from the venue is all you need, we will say so.
