Temporary Electrical Systems (TES) is covered by BS 7909 (Code of practice for temporary electrical systems for entertainment and related purposes), BS 7671 may also apply.
Temporary electrical systems are electrical systems designed and installed for a very short duration, such as for an event, from a large live concert to the local village fate.
Even though these types of electrical systems are generally only in use for a very short duration it is still a requirement to carry out the relevant testing before handing over the electrical system to the event organiser, temporary electrical installation certificates based on BS 7909 should be produced and handed to the relevant event personnel while retaining a copy for your own records.
BS 7909 is a guide to setting up and managing safe and suitable temporary electrical systems at entertainment or similar events. BS 7909:2023 is a full revision of the standard, bringing it up to date and making it more user-friendly. – Source BSI.