If you run or manage a commercial building in the UK, emergency lighting isn't optional — it's a legal duty. Here's what actually applies to you.
UK emergency lighting is governed by the Regulatory Reform (Fire Safety) Order 2005 and installed to the British Standard BS 5266-1. In practice that means: escape routes and specific high-risk areas must have emergency lighting that comes on automatically when the mains fails and stays lit for a minimum of 3 hours (or 1 hour in limited cases), and the system must be tested monthly and given a full duration test annually, with records kept.
That paragraph is the whole duty in miniature. The detail — where exactly, what type, and who carries the can — is what keeps building owners up at night. Let's clear it up.
1. Where the law actually applies
Emergency lighting is required in effectively all non-domestic premises: workplaces, shops, offices, factories, care homes, pubs, HMOs and the common areas of blocks of flats. It is not generally required inside an individual private dwelling — but the shared escape routes of a converted or purpose-built block are.
The “responsible person” under the Fire Safety Order — usually the employer, owner or occupier — must ensure a suitable emergency lighting system is provided and maintained. That word “maintained” is doing a lot of work, and we'll come back to it.
2. What has to be lit
BS 5266 focuses on illuminating the means of escape and the equipment that supports it. In plain terms, you need emergency lighting at and along:
Escape routes and corridors. Every change of direction and every intersection. Each final exit door and the route to it. Stairways (each flight lit directly). Changes of floor level. Fire alarm call points and firefighting equipment. Plant rooms and lift cars. And “open areas” over 60m² (anti-panic lighting), so people can find the exits.
Directional signage is a core part of this. The Knightsbridge EMRUNR Emergency Exit Sign carries the standard running-man legend with a right-facing arrow — the ISO-format pictogram people recognise instantly, even in smoke. Signs like this mark the direction of travel at each decision point on the escape route, which is exactly what BS 5266 asks for.
One practical point on signage: the size of the pictogram sets how far away it can be read. As a rough rule, a standard sign is legible at around 100 times its height — so a 185mm sign reads at roughly 18 metres. Long corridors need bigger signs or more of them, not one small sign at the far end that nobody can make out through smoke.
And one provision that gets forgotten more often than any other: if your building has refuge areas — the protected waiting points on escape stairs for people who can't evacuate unaided — those refuges need emergency lighting too, plus a means of two-way communication so the person waiting can call for help and be heard. Our disabled refuge alarms range covers exactly that side of the system.
3. The 3-hour rule and maintained vs non-maintained
Two definitions settle most arguments on site.
Duration: emergency lighting must run on its own battery for a minimum rated duration after mains failure — 3 hours for most premises (anywhere the public sleep, or where evacuation may be delayed), and 1 hour only where premises are evacuated immediately and not reoccupied until recharged. When in doubt, spec 3-hour. It's the safe default and what most fire risk assessments expect.
Maintained vs non-maintained: a maintained fitting is lit all the time and stays lit on battery when the mains drops — used where areas are occupied in darkness, like cinemas. A non-maintained fitting is off in normal use and only illuminates when the mains fails — the usual choice for offices and corridors that are normally lit anyway.
To bring an existing fitting up to standard, the Knightsbridge BPLEDEM 14W LED Emergency Gear Tray is a tidy route — a 230V, cool-white LED gear tray putting out 1480 lumens with a 3-hour emergency backup, designed as a replacement for older 2D 28W fittings. It gives you the mandated 3-hour duration in a familiar housing.
Trade Tip: The mistake we see most often is a building full of emergency fittings and not a single one covering the final exit door from the outside, or the external route to a place of safety. The regs care about getting people all the way out — not just to the door. Walk the escape route in the dark, in your head, and light every point where you'd hesitate.
4. Testing — the part that gets buildings in trouble
Installing the system is one duty. Proving it works is the one that actually gets audited. BS 5266 sets a testing regime, and it is not optional:
Monthly: a short “flick test” — operate the test facility, confirm every luminaire and exit sign illuminates, restore the supply. Annually: a full-duration test — run the system on battery for its full rated 3 hours to prove the batteries genuinely hold up, then confirm they recharge. Every test is logged; the logbook is what an inspector asks for first.
You can't test a system safely without a proper isolation point, which is where the Knightsbridge GDM007MW Emergency Test Key Module earns its place. It's a 20AX 2-way single-pole key switch module, marked “EMG LTG TEST,” letting authorised staff simulate a mains failure to that circuit with a key — so the monthly test is quick, controlled and can't be flicked by a passer-by.
Trade Tip: Keep the test key on the logbook, not on the caretaker's general keyring. A locked-off test switch with a dedicated key is how you prove tests were deliberate and controlled — and it stops the circuit being isolated by accident.
Explore our full emergency lighting range and emergency exit signs for the fittings, signage and test gear to build a compliant system.
5. Summary table
| Requirement | The standard |
|---|---|
| Governing law | Regulatory Reform (Fire Safety) Order 2005 |
| Design standard | BS 5266-1 |
| Minimum duration | 3 hours (1 hour in limited cases) |
| Where | Escape routes, exits, stairs, changes of level, call points, open areas >60m² |
| Monthly test | Short function test of every luminaire & sign |
| Annual test | Full 3-hour duration test, logged |
| Responsible person | Employer / owner / occupier |
6. Expert Help in the West Midlands
WME has supplied Birmingham's trade with emergency and commercial lighting from Villa Road since 1975. If you're specifying a system for a shop, office or HMO and you're not sure whether you need maintained or non-maintained, 1-hour or 3-hour, or how to set up a proper test regime, bring your floor plan to the counter. We'll help you spec it to BS 5266 without gold-plating it — the right kit for the building, and the test gear to keep it compliant.
Frequently asked questions
How often should emergency lighting be tested?
Monthly for a short function test of every fitting and exit sign, plus a full-duration test once a year that runs the system on battery for its rated 3 hours. Every test must be recorded in the logbook.
How long must emergency lighting stay on?
A minimum of 3 hours after a mains failure for most premises. A 1-hour rating is only acceptable where the building is evacuated immediately and not reoccupied until the batteries have recharged.
Is emergency lighting a legal requirement in the UK?
Yes, for non-domestic premises. The Regulatory Reform (Fire Safety) Order 2005 places the duty on the responsible person, and systems are designed and maintained to BS 5266-1.
This is a general guide to UK emergency lighting requirements, not a substitute for a fire risk assessment. Emergency lighting design, installation and certification should be carried out by a competent person to BS 5266-1.