How Should Emergency Lighting Be Maintained? Standards and Practical Guide
Short answer
Emergency lighting systems must be tested regularly under TS EN 1838 and the Turkish Regulation on the Fire Protection of Buildings, and the results entered in the logbook: a short functional test, a monthly test of 3–5 minutes and an annual full-discharge test that measures the battery's real capacity. Luminaires must switch on within a few seconds of a mains failure and operate for at least 1 hour, or 3 hours in high-risk areas.
Emergency lighting systems are the last line of defence for building occupants, coming into play at the most critical moment. If these systems do not work in emergencies such as fire, earthquake, power failure or explosion, people are left in the dark in panic. Emergency lighting is therefore not a piece of equipment to be forgotten after purchase but a critical safety system that must be carefully maintained, tested and documented.
What is emergency lighting and why is it necessary?
Emergency lighting is a lighting system that switches on automatically when the mains supply fails or an abnormal situation occurs, making the safe evacuation of people in the building possible. It falls into two basic categories:
- Escape route (signage) lighting: Luminaires with green pictograms that mark exit doors, stairs and the evacuation route. They show clearly which way people should go in the dark.
- Safety lighting (general emergency): Luminaires that provide a defined illuminance in corridors, stairs, plant rooms and assembly areas. They allow evacuation to take place safely in a panic situation.
In Türkiye, emergency lighting systems are mandatory under TS EN 1838 (the emergency lighting standard), IEC 60598-2-22 and the Regulation on the Fire Protection of Buildings, and are inspected at defined intervals.
Battery life and capacity requirements
The most critical component of emergency luminaires is the internal battery or central battery system. According to TS EN 1838:
- Minimum operating time for escape lighting: 1 hour
- For high-risk areas (factories, hospitals, residential blocks): 3 hours
- Switch-on time (how quickly the light comes on when the mains fails): 5 seconds or less
- Minimum illuminance on escape routes: 1 lux (centre line) / 0.5 lux (edges)
- In open and large areas (anti-panic): 0.5 lux, evenly distributed
Mandatory test procedures
The standards specify three different test intervals for emergency lighting systems:
1. Daily/weekly functional test
A short (usually a few seconds) simulated mains failure is used to check whether all luminaires switch on. In most modern systems this test is carried out automatically by an automatic test module and the results are logged in the system. In manual systems it is carried out by the responsible building staff and recorded.
2. Monthly test
In this test, carried out every month, a longer mains failure is simulated (3–5 minutes). It is checked whether the luminaires operate at full performance for the set period, how visible the pictogram lights are and what the lumen output is. The results must be documented and entered in the logbook.
3. Annual full-discharge test
In this most comprehensive test, the whole system imitates a real emergency once. The mains is cut off completely and the real capacity of the batteries is measured; it is verified whether the system operates at full performance for the legal minimum duration (1 or 3 hours). After this test, enough time must be allowed for the batteries to recharge (usually 24 hours).
How do you know when to replace the battery?
The lifetime of emergency lighting batteries varies with the luminaire type and the technology used:
| Battery type | Typical life | Characteristics |
|---|---|---|
| Nickel-cadmium (NiCd) | 4–6 years | High temperature tolerance; restricted by environmental legislation |
| Nickel-metal hydride (NiMH) | 3–5 years | Less toxic than NiCd |
| Lithium iron phosphate (LiFePO4) | 8–10 years and more | Light, compact; expensive but economical in the long term |
The most reliable sign that a battery needs replacing is that it cannot complete the expected duration in the annual full-discharge test. Fault LEDs on the luminaires or warnings from a central monitoring system also allow battery problems to be detected early.
Common maintenance mistakes
- Not recording test results: Buildings without a logbook face serious sanctions in legal inspections.
- Delays in replacing damaged pictograms: Faded or broken pictogram luminaires no longer guide people during evacuation.
- Covering luminaires: Emergency luminaires covered during storage or refurbishment are dangerous in terms of heat and useless in an emergency.
- Not testing the central battery system in a simulated mains failure: Not just the luminaires but the whole system (cables, distribution board, battery groups) must be tested together.
Automatic testing: the modern solution
Today, advanced emergency lighting systems carry out all tests on a programmed basis thanks to built-in automatic test modules and send the results to central software via DALI or RS485. The building manager can see the status of all luminaires, battery health and test results instantly from a computer or tablet. Faulty luminaires are detected immediately, reports are generated automatically and legal obligations are met easily. In large buildings these systems offer significant advantages in both labour savings and safety.
Conclusion
Emergency lighting systems are meaningful not only at the moment of purchase but when they are kept ready to save lives every day after installation. Regular testing, record-keeping, battery replacement and automatic monitoring are the basis for both meeting legal obligations and genuinely safeguarding people. Remember: an emergency lighting system that is not tested is equivalent to no system at all.
Frequently Asked Questions
How long should emergency lighting stay on?
At least 1 hour for escape lighting; an operating time of 3 hours is required in high-risk areas such as factories, hospitals and residential blocks.
When should an emergency lighting battery be replaced?
The most reliable sign is that the battery cannot complete the required duration in the annual full-discharge test. Typical lifetimes are 4–6 years for NiCd, 3–5 years for NiMH and 8–10 years or more for LiFePO4 batteries.
Should emergency lighting test results be recorded?
Yes. Every test and battery replacement should be entered in the logbook; buildings without records may face sanctions during inspections. Systems with automatic test modules keep this record themselves.