Government guidance for blocks of flats describes a short functional test of emergency lighting each month and a full-duration discharge test once a year. For a typical three-hour system, the annual test should confirm that the fittings can operate for the full three-hour duration.
Monthly functional testing
The monthly test is intended to establish that the emergency fittings operate when the normal supply is simulated as having failed. It is a short functional test, not a full battery discharge. A suitable test switch or other test facility should be available.
Annual full-duration testing
Government guidance for purpose-built and small blocks describes a full-duration discharge test once a year. This should be carried out by a competent contractor where appropriate and should confirm that the batteries can support the fittings for their intended duration.
Allow for battery recharge
A full-duration test temporarily depletes the batteries. Testing should therefore be planned so that the building is not left without effective emergency lighting while batteries recharge. If necessary, alternative arrangements should be considered for the recharge period.
Keep a record
Record the date of the test, any failures identified and what was done about them. A servicing visit or invoice should not be the only record where the client needs evidence that the system passed the required test.
Do not impose a system where it is not needed
Not every very small block necessarily requires emergency escape lighting. Government guidance recognises limited circumstances where adequate borrowed light may be sufficient. The need for emergency lighting should therefore be established from the building, its escape routes and the fire risk assessment rather than assumed in isolation.