Guide
Lighting requirements for business premises
Key lighting requirements for business premises, covering workplace lighting standards under the Workplace Regulations 1992, emergency lighting duties, and Part L energy efficiency standards for non-domestic buildings.
This reference covers the three main lighting obligations for business premises: workplace lighting standards, emergency lighting, and energy efficiency requirements under Part L of the Building Regulations.
Workplace lighting standards
Regulation 8 of the Workplace (Health, Safety and Welfare) Regulations 1992 requires every workplace to have suitable and sufficient lighting. This must be natural light, so far as is reasonably practicable, supplemented by artificial lighting where necessary.
The regulations do not prescribe specific lux levels, but HSE guidance and the Chartered Institution of Building Services Engineers (CIBSE) provide recommended illuminance levels for different tasks:
- General offices and retail areas - 300 to 500 lux
- Drawing offices and detailed inspection - 500 to 750 lux
- Warehouses and storage areas - 100 to 200 lux
- Corridors and circulation areas - 50 to 100 lux
- Outdoor working areas - 20 to 50 lux
Lighting must not cause glare, flicker, or stroboscopic effects that could cause discomfort or safety hazards. Windows and skylights must be clean and unobstructed. Where workstations are near windows, adjustable blinds or screening should be provided to control glare.
Emergency lighting
The Regulatory Reform (Fire Safety) Order 2005 requires the responsible person to provide emergency escape lighting where necessary to safeguard occupants. In practice, this means almost all workplaces need emergency lighting.
Emergency lighting must illuminate escape routes, exit signs, fire alarm call points, firefighting equipment locations, and changes in floor level. It must activate automatically if the normal supply fails and provide sufficient illumination for safe evacuation.
Testing schedule
Emergency lighting requires regular testing to the requirements of BS 5266-1:
- Monthly - brief functional test (flick test) to confirm each luminaire operates on battery. Record the date, person carrying out the test, and any defects found.
- Annually - full rated duration test (typically 3 hours for non-maintained systems). The system must operate for its full rated duration. Record results and replace any luminaires that fail.
Automatic test systems are available that carry out these tests without manual intervention and produce downloadable reports, reducing the administrative burden.
Part L lighting efficiency
When you install or replace lighting in a non-domestic building, Part L of the Building Regulations sets minimum energy efficiency standards. These requirements apply to new buildings, extensions, and when you are replacing luminaires as part of a refurbishment.
LED retrofit considerations
When upgrading from fluorescent or halogen lighting to LED, the replacement luminaires must meet Part L minimum efficacy standards. A like-for-like swap that reduces overall efficacy below the Part L threshold is not compliant.
In practice, modern LED luminaires comfortably exceed Part L requirements, but you must also ensure that the lighting control system is updated to include occupancy sensing, daylight dimming, and time scheduling where these were not previously installed.
Natural light
The Workplace Regulations require natural light so far as is reasonably practicable. This is a separate obligation from Part L efficiency. Blocking windows to save energy or improve thermal performance must be balanced against the requirement to provide natural light to workstations.
For detailed guidance on how to manage your electrical installations, see Electrical safety in your business premises.