Emergency lighting in residential blocks: Is your current testing still enough?

The latest revision of BS 5266-1, introduced in October 2025, recommends photometric verification of emergency lighting systems initially and at intervals not exceeding five years.

Often referred to as a LUX survey, this goes beyond simply checking whether emergency fittings work. It measures the actual levels of emergency illumination being achieved throughout the building.

For those managing residential blocks, it is an important distinction.

A working light doesn't always tell the whole story

Monthly and annual testing remain an essential part of emergency lighting maintenance. They help confirm that fittings operate when the normal lighting supply fails and that they continue operating for the required duration.

But imagine walking a communal escape route during a power cut.

It isn't enough for individual green lights to be visible overhead. Residents need sufficient illumination to safely navigate corridors, stairs, changes in level, turns and other potential hazards.

This is what photometric verification looks at.

A fitting switching on tells you it works. It doesn't necessarily tell you whether there is enough light to get residents safely along the escape route.

Why could things have changed?

Even where an emergency lighting system was correctly designed and installed, buildings rarely remain exactly the same.

Fittings age, light output can reduce and diffusers can deteriorate. Communal areas can also change over time – doors are replaced, layouts altered, decorations changed and new equipment installed.

Individually these changes may seem relatively minor, but over several years the lighting being achieved may no longer be exactly what was originally designed.

This is why periodically measuring actual light levels can provide valuable reassurance.

Does this mean another annual test?

No. The five-year photometric verification recommendation doesn't replace the familiar monthly functional or annual full-duration tests. It sits alongside them.

For managing agents, the practical first step is therefore not to start arranging additional testing across an entire portfolio tomorrow.

Instead, look at the information you already hold.

When was the emergency lighting system installed or last upgraded? Has a photometric assessment previously been completed? Have communal layouts changed? Do you have the original design information and records?

If the answer to some of those questions is unclear, it is worth discussing the building with your emergency lighting contractor.

And what if the results identify a problem?

A LUX survey does not automatically mean a building needs a new emergency lighting system.

In many cases, verification may simply provide evidence that the existing system continues to perform appropriately.

Where an issue is identified, however, measured results make it easier to understand exactly where the problem lies. Rather than assuming an entire system needs replacing, improvements can be considered based on the areas that actually require attention.

For managing agents balancing safety responsibilities, maintenance programmes and service charge expenditure, that evidence is valuable.

Building safety is increasingly about being able to demonstrate that systems continue to perform as intended – not simply that a test has been completed.

Emergency lighting has one very important job to do. The latest guidance gives us another way of making sure it can still do that job when residents need it most.

Emergency lighting is a fundamental life-safety provision within residential buildings, particularly across communal corridors, stairwells and lobbies. Historically, compliance has centred on ensuring emergency luminaires operate during a power failure, supported by monthly functional tests and annual full-duration testing.

However, updated emergency lighting standards are placing greater emphasis on demonstrable performance. The question is no longer simply whether emergency lighting switches on, but whether it continues to provide adequate illumination when it is needed.

From functionality to performance

Routine testing remains essential. It confirms that fittings illuminate following a loss of normal supply and remain operational for their required duration.

What it does not necessarily demonstrate is how much usable light is actually reaching an escape route.

Emergency lighting performance can change over time. LED output gradually reduces, batteries age and diffusers deteriorate. Buildings evolve too: doors are replaced, corridors reconfigured and finishes or layouts altered.

A system can therefore remain operational while its actual lighting performance differs from the conditions under which it was originally designed.

This distinction is important. A luminaire illuminating during a functional test tells us that it works; it does not, on its own, demonstrate the photometric performance of the emergency lighting system as a whole.

The role of photometric verification

BS 5266-1:2025 recommends photometric verification of emergency lighting systems initially and at intervals not exceeding five years.

Often referred to as a LUX survey, the process assesses the actual illumination provided by the emergency lighting system and helps verify that its photometric performance remains appropriate.

This can be particularly relevant within residential corridors and stairwells, where door recesses, changes in width, turns and steps can affect the distribution of light.

Crucially, photometric verification does not replace monthly functional tests or annual full-duration testing. Instead, it provides an additional layer of assurance by considering the performance of the system as a whole.

In many buildings, verification will confirm that the existing system remains adequate. Where shortcomings are identified, measured results enable managing agents and Responsible Persons to understand where improvements may be required and plan them proportionately.

What should managing agents consider?

The message should be one of awareness rather than alarm.

A sensible starting point is understanding what information already exists. When was the system designed or last upgraded? Has the communal layout changed? Are the original designs available? Has photometric verification previously been undertaken?

These questions help establish what, if anything, requires further review.

Photometric verification does not automatically indicate non-compliance, nor does it mean existing systems are inadequate. What it provides is evidence – allowing decisions to be based on measured performance rather than assumption.

As building safety becomes increasingly evidence-led, demonstrating that life-safety systems not only operate but continue to perform as intended is becoming an important part of good residential block management.

Jordan Begg
Co-Founding Director – Future Group of Companies