Why office lighting goes wrong
Most office lighting problems are not about darkness. They come from uneven light, glare on screens and lighting that no longer matches the layout. Typical findings on our surveys include:
- Desks moved under a refit so that workstations now sit between luminaire rows rather than beneath them.
- LED panels retrofitted at a higher spacing than the old fittings, leaving dim bands and poor uniformity.
- Bright reflections on monitors from unshielded downlights or from low-angle sun through unblinded glazing.
- Meeting rooms and breakout areas lit for atmosphere, then used for long laptop sessions.
- Failed or dimmed drivers that nobody has reported because the change happened gradually.
Staff complaints of eye strain or headaches are often the first sign. Our guide to why employees complain about lighting covers the usual causes.
The standards and lux targets that apply
The legal duty comes from regulation 8 of the Workplace (Health, Safety and Welfare) Regulations 1992, which requires suitable and sufficient lighting. For offices with screen users, the Health and Safety (Display Screen Equipment) Regulations 1992 add a requirement for workstation assessments that cover lighting and glare. HSE guidance HSG38 Lighting at work explains how to meet these duties, and BS EN 12464-1:2021 provides the recognised task-by-task design values. CIBSE SLL LG7 gives detailed guidance specific to offices.
| Office area or task | Maintained illuminance (BS EN 12464-1:2021) |
|---|---|
| Writing, typing, reading, data processing | 500 lx |
| CAD work stations | 500 lx |
| Conference and meeting rooms | 500 lx |
| Filing, copying | 300 lx |
| Reception desk | 300 lx |
| Archives | 200 lx |
| Circulation areas and corridors | 100 lx |
Illuminance is only part of the picture. For desk tasks the standard also expects a uniformity (Uo) of at least 0.60 across the task area, colour rendering of Ra 80 or better and a glare limit (UGR) of 19. The 2021 edition added higher "modified" values for demanding conditions, plus guidance on lighting walls, ceilings and faces so rooms do not feel gloomy even when the desk reading is acceptable. More detail is in our office lighting standards page and the DSE lighting guide.
Who asks for evidence
HSE and local authority inspectors
Most offices fall to local authority environmental health officers rather than HSE for health and safety enforcement. Neither will usually demand a lux report on a routine visit, but after a complaint or a DSE-related illness claim they will ask how you know the lighting is adequate. A dated set of measurements is the clearest answer.
Landlords, tenants and insurers
Lux readings are increasingly requested at lease start and end, during dilapidations negotiations and when a landlord carries out an LED upgrade across shared floors. Insurers and employers' liability claims handlers may ask for them after an incident. Fire risk assessors under the Regulatory Reform (Fire Safety) Order 2005 will also look for evidence that emergency escape lighting works.
What we measure in an office survey
Our surveyors follow the measurement grid approach described in BS EN 12464-1:2021, using a calibrated lux meter. On a typical floor we:
- Record maintained illuminance on the working plane at each desk cluster, meeting room and circulation route.
- Calculate average illuminance and uniformity for each zone, not just spot readings.
- Note daylight contribution and, where it matters, take readings with blinds closed or after dark so results reflect the worst case.
- Identify glare sources affecting screens and record luminaire types, failures and obvious dimming.
- Optionally check emergency escape lighting against BS 5266-1:2025 and BS EN 1838:2024.
The report compares every zone with its target value, flags anything below standard and gives practical remedial suggestions. If you have not seen one before, our explainer on reading a lux survey report walks through each section.
After a refit or LED upgrade
An office refurbishment is the most common trigger for failure. New desk layouts, partitions and lower-output LED retrofits can all push areas below 500 lx without anyone noticing. A post-installation survey proves the new scheme performs as designed and gives you a baseline for future checks. See can an LED upgrade reduce compliance? for the common pitfalls.
Book an office lighting survey
We survey offices across London and the South East, from single tenanted floors to multi-storey headquarters. Our office lux survey service starts from £175 for a single floor up to 250 m², with the final price confirmed before booking. Book an office lighting survey online and we will confirm a date and scope.
Frequently asked questions
What lux level is required for an office desk?
BS EN 12464-1:2021 recommends 500 lux maintained illuminance for writing, typing, reading and data processing, with uniformity of at least 0.60 across the task area. UK law requires suitable and sufficient lighting, and this standard is the recognised benchmark for showing it.
Is office lighting testing a legal requirement?
There is no law that names a test frequency, but employers must provide suitable lighting under the Workplace Regulations 1992 and assess screen workstations under the DSE Regulations 1992. A lux survey is the most reliable way to show you have met those duties.
Do LED upgrades make offices compliant automatically?
No. LED retrofits can reduce light on desks if fittings are spaced differently, have narrower beam angles or lower output than the originals. A survey after installation confirms the new scheme meets 500 lux at workstations.
How long does an office lux survey take?
A single floor of up to 250 square metres usually takes a few hours on site, with the written report following afterwards. Larger or multi-floor buildings are scoped and priced before booking.