Emergency Lighting Testing — What BS 5266 Actually Requires
BS 5266 emergency lighting testing is simple in principle and frequently fumbled in practice. Here is the cadence, the test specifics and the documentation enforcers ask for.
The testing cadence
Under BS 5266-1, emergency lighting must be tested:
- Monthly — Short-duration functional test (every luminaire operated for a short period)
- Annually — Full 3-hour duration discharge test
The monthly functional test
A monthly test verifies that every luminaire:
- Activates on loss of mains
- Illuminates correctly
- Returns to normal on restoration of mains
This is typically achieved by operating a key-switch isolator or breaker for each circuit. Self-test addressable systems automate this and provide an electronic log.
The monthly test should be recorded in the logbook with:
- Date
- Test method
- Any luminaire failures and remedial action
- Sign-off by competent person
The annual 3-hour test
The annual test verifies that every luminaire achieves the full 3-hour duration required by BS 5266-1. The test must:
- Be carried out at a time of low building occupancy (typically out-of-hours)
- Run for the full 3 hours
- Be witnessed and recorded
- Identify any luminaires that fail to achieve duration
Luminaires failing the 3-hour test must be replaced. The lifecycle of an emergency lighting battery is typically 4-5 years; after that, duration failures accelerate.
Self-contained vs central battery systems
Most modern installations use self-contained luminaires — each fitting has its own battery. Testing is per-luminaire.
Central battery systems use a single battery bank serving multiple luminaires. Testing is at the battery level and is more invasive — often requires the battery to be discharged and recharged.
Self-test addressable systems automate both monthly and annual tests and produce a digital report. These are the gold standard in 2026 — retrofit cost typically pays back inside 3 years through reduced testing labour.
What enforcement officers check
- Logbook current with monthly test records
- 3-hour test certificate in date
- All luminaires functional on walk-through
- Exit signs illuminated (where applicable)
- Lux levels meeting BS EN 1838 (1 lux centreline on escape routes)
Common failures
- Old battery packs failing to achieve 3-hour duration
- Modified ceilings burying luminaires above suspended grids
- Refurbishments removing or replacing luminaires without re-certifying coverage
- Self-test systems left in fault state indefinitely
MetroFire delivers BS 5266 emergency lighting design, install and 3-hour testing across London and Essex. Book a test.
