When the mains power fails in a commercial building, your emergency lighting system becomes the difference between a safe evacuation and a dangerous situation. For architects, lighting designers, and electrical engineers working on UK commercial projects, getting emergency lighting design right means navigating a complex landscape of British Standards, building regulations, and practical installation challenges.
This guide walks you through everything you need to know about designing compliant emergency lighting systems for commercial buildings in the UK. From understanding the latest BS 5266-1:2025 requirements to selecting the right luminaires and testing systems, 299 Lighting has drawn on our experience delivering emergency lighting design across thousands of commercial fit-outs to bring you practical, specification-ready guidance.
Emergency lighting activates when the normal mains power supply fails, allowing building occupants to evacuate safely. In commercial buildings, this means illuminating escape routes, exit doors, fire alarm call points, and firefighting equipment so people can see hazards, changes in level, and directional signage.
Beyond evacuation, emergency lighting serves several additional purposes. It reduces panic in enclosed spaces like lifts or high-occupancy areas. It enables occupants to complete dangerous processes before evacuating. And it can allow certain activities to continue through standby lighting if evacuation is not required.
The Regulatory Reform (Fire Safety) Order 2005 makes it a legal requirement for all non-domestic premises to install emergency lighting where appropriate. As the building's Responsible Person, you carry the duty to ensure systems are properly designed, installed, and maintained.
Emergency lighting design in the UK sits at the intersection of several key standards and regulations. Understanding how these fit together helps you specify systems that meet compliance requirements while supporting your design intent.
The British Standards Institution published the fully revised BS 5266-1:2025 in November 2025, replacing the 2016 edition. This standard now covers three distinct types of emergency lighting:
The expanded scope reflects modern building use. In many commercial premises, evacuation is not the only consideration. Some occupants may need to remain in place, or essential operations may need to continue safely.
The CIBSE Lighting Guide 12 (2022) complements BS 5266-1 by providing detailed design guidance for practitioners. LG12 covers risk assessment methodology, design calculations, equipment selection, and the commissioning process.
As the guide notes, emergency lighting is not a complex lighting design problem, but it is a difficult design management problem. Premises must remain compliant throughout their occupied life, requiring careful coordination between designers, installers, and building operators.
This order places the legal responsibility for fire safety, including emergency lighting, on the Responsible Person. In most commercial buildings, this is the employer, owner, or occupier who has control over the premises.
The Responsible Person must ensure emergency routes and exits requiring illumination are fitted with emergency lighting of adequate intensity. They must also maintain systems in proper working order and arrange for regular testing in accordance with BS 5266.
Before specifying any emergency lighting system, you need to carry out a risk assessment. This determines the category of premises, the hazard level, and the degree of occupant familiarity with escape routes.
Your assessment should evaluate building layout and escape route complexity, occupancy levels and characteristics, activities carried out in different areas, normal lighting conditions when occupied, and the potential consequences of lighting failure in each zone.
Buildings where occupants are unfamiliar with the layout, such as hotels, shopping centres, and entertainment venues, typically require more extensive emergency lighting than workplaces where staff know the escape routes well.
The risk assessment should produce documentation showing proposed escape routes, locations of fire alarm call points and firefighting equipment, areas requiring anti-panic lighting, high-risk task areas, and the duration required for battery backup. This documentation supports your emergency lighting design and demonstrates due diligence to fire safety inspectors.
BS 5266-1 and EN 1838 set specific illumination levels that your emergency lighting must achieve. These minimum values apply along the centre line of defined escape routes and across open areas.
Designated escape routes up to 2 metres wide require a minimum of 1 lux at floor level along the centre line. The uniformity ratio should be no greater than 40:1 to avoid pools of light and dark patches that could obscure hazards. For wider routes, you should treat them as open areas.
Because stairwells present increased hazards, they require a minimum of 2 lux illumination. This higher level helps occupants see steps, handrails, and changes of direction clearly during evacuation.
Open areas larger than 60 square metres that are not part of a designated escape route still need emergency lighting to prevent panic. The minimum illumination is 0.5 lux across the floor area, with a uniformity ratio no greater than 40:1.
Where occupants are involved in potentially dangerous activities, higher illumination levels may be needed to allow safe shutdown procedures. The specific requirements depend on the task being performed.
Choosing between maintained and non-maintained fittings is one of the most important decisions in emergency lighting design. The right choice depends on building type, occupancy patterns, and normal lighting conditions.
Maintained fittings operate continuously as part of normal room lighting. They run on mains power during normal operation but switch to battery backup when power fails, continuing to provide illumination at a reduced output level.
Maintained lighting is required in premises where normal lighting is routinely dimmed or switched off while occupied. This includes cinemas, theatres, nightclubs, and bars. It is also commonly used in public assembly buildings like shopping centres and leisure facilities where occupants may be unfamiliar with escape routes.
Non-maintained fittings remain off during normal operation. They only illuminate when the mains power fails, powered by batteries that charge continuously from a trickle supply. These fittings are typically used in workplaces like offices, factories, and schools where occupants are familiar with the building and escape routes are clearly visible under normal lighting.
Non-maintained systems have lower energy consumption since they only operate during emergencies. This makes them a practical choice where maintained lighting is not specifically required.
Sustained fittings include two separate lamps: one operating on mains supply for normal lighting, and another that activates from battery supply during power failure. Combined or switchable fittings can operate in either maintained or non-maintained mode, offering flexibility for buildings with mixed requirements.
Effective emergency lighting design places luminaires where they provide maximum safety benefit. The positioning requirements are specified in BS 5266-1 and should be verified through spacing calculations.
Emergency luminaires must be positioned at or near each exit door, at changes of direction along escape routes, at changes of floor level including stairs and ramps, at intersections of corridors, outside and near each final exit, and near first aid posts and firefighting equipment.
Additionally, luminaires should be placed near fire alarm call points and safety signs to ensure these can be seen and operated during power failure.
Manufacturers publish spacing tables for their emergency luminaires based on mounting height and room geometry. These tables show the maximum distance between fittings while maintaining minimum illumination levels. For irregular spaces or where spacing tables cannot be applied directly, computer-based lighting calculations are needed.
At 299 Lighting, we support all our emergency lighting products with photometric data, spacing information, and LDT files for software calculations. Our team can prepare full emergency lighting calculations for your project, ensuring compliant coverage across all escape routes and open areas.
The emergency lighting market offers a range of product types suited to different applications. Understanding the options helps you specify fittings that meet both compliance requirements and aesthetic considerations.
Bulkhead luminaires are robust, surface-mounted fittings commonly used in back-of-house areas, plant rooms, car parks, and external escape routes. They provide good light output and are available in IP65-rated versions for damp or dusty environments.
For design-led spaces where visible emergency fittings would compromise aesthetics, emergency conversion modules can be integrated into standard downlights. These conversions allow your general lighting to double as emergency lighting, maintaining design intent while meeting compliance. 299 Lighting supplies integrated emergency options across our downlight range, with UK-made conversion kits and four-year warranties.
Modern linear lighting systems can incorporate emergency modules that maintain illumination along the luminaire length during power failure. This approach works well in offices and commercial spaces where linear lighting forms the primary lighting scheme.
Illuminated exit signs are required at every designated exit. These may be maintained (always lit) or non-maintained (lit only during emergency), depending on normal lighting conditions. Signs must comply with safety sign regulations and be positioned to be visible from the relevant escape route.
Emergency lighting must be tested regularly to confirm it will function when needed. BS 5266-1 specifies testing requirements, and modern systems offer automated options to reduce the maintenance burden.
Without automated testing, emergency lighting requires monthly functional tests (a brief activation to confirm operation) and annual full-duration tests (running on battery for the rated duration, typically three hours). Results must be recorded in a logbook for inspection.
Self-test luminaires incorporate microprocessor controls that automatically perform functional tests and duration tests at programmed intervals. LEDs or other indicators show pass/fail status, reducing the need for manual intervention. Self-test fittings still require periodic inspection to check indicators and log results.
Larger installations often benefit from central test systems that monitor and test all connected luminaires from a single controller. These systems can schedule tests automatically, compile reports, and flag faults for maintenance. DALI-based addressable systems enable sophisticated monitoring and integration with building management systems.
299 Lighting offers emergency fittings with self-test functionality and DALI reporting options, giving you flexibility to match the testing approach to your project requirements and client preferences.
Proper documentation demonstrates compliance and supports the Responsible Person in meeting their legal duties. The design and installation process should produce several key documents.
Your design package should include the emergency lighting risk assessment, escape route drawings with luminaire positions, lighting calculations showing compliance with illumination requirements, product datasheets and photometric data, and a schedule of emergency luminaires with specifications.
The installation process produces test certificates confirming electrical safety, commissioning records showing each luminaire functions correctly, an emergency lighting completion certificate, and as-installed drawings reflecting any site changes.
Once the system is handed over, the building operator needs an operation and maintenance manual, a test logbook for recording monthly and annual tests, and a maintenance schedule with lamp and battery replacement intervals.
We have been supplying emergency lighting systems and design support since the start of our business. Working alongside architects, consultants, and contractors on large-scale CAT A fit-outs and commercial refurbishments, we understand the practical challenges of delivering compliant emergency lighting that integrates with your overall lighting scheme.
Our range includes standalone emergency bulkheads and spotlights, integrated emergency options for linear, suspended, and downlight luminaires, self-test modules and DALI reporting systems, and exit signage compliant with British Standards. All products are supported with photometric data, spacing tables, and technical specifications.
We offer full emergency lighting design services, including risk assessment support, luminaire spacing calculations, and compliance documentation. Our LIA-accredited Light Engineers can review your scheme, recommend products, and prepare the technical submissions needed for building control approval.
Want to know more about what 299 Lighting can do for your project? Our team can take you through all your options to suit your timeline and budget in an initial consultation.
After delivering thousands of commercial projects, we have seen how small oversights can cause compliance issues or installation problems. Here are the most common mistakes to avoid.
Relying on general assumptions rather than proper spacing calculations often results in insufficient coverage. Always verify your layout with manufacturer spacing data or calculated lux levels.
Emergency lighting should complement your general lighting design, not conflict with it. Consider how emergency fittings will look alongside your primary luminaires, and explore integrated options where appropriate.
Fittings installed in difficult-to-reach locations make testing and battery replacement problematic. Specify accessible positions or ensure automated testing is specified from the outset.
Failing to produce proper design documentation and handover records leaves the Responsible Person without the evidence needed to demonstrate compliance. Build documentation requirements into your project workflow.
Emergency lighting design requires balancing regulatory compliance with practical installation considerations and design intent. The revised BS 5266-1:2025 reflects the evolving needs of modern buildings, expanding coverage to include local area and standby lighting alongside traditional escape lighting.
For architects, lighting designers, and electrical engineers, getting emergency lighting right means starting with a thorough risk assessment, selecting appropriate luminaires for each application, and producing documentation that supports ongoing compliance. Working with a lighting supplier who understands both the technical requirements and the commercial realities of fit-out projects makes this process more manageable.
At 299 Lighting, we partner with project teams to deliver emergency lighting solutions that meet British Standards while maintaining design quality. From initial consultation through to product supply and technical support, we are here to help you achieve compliant, aesthetically appropriate emergency lighting for your commercial project. You Imagine It. We Make It Happen.
Emergency escape routes require a minimum of 1 lux at floor level along the centre line. Stairwells need at least 2 lux due to the increased hazard of changes in level. These requirements come from BS 5266-1 and EN 1838.
Maintained lighting is required where normal lighting is dimmed or off while occupied, such as cinemas and theatres. Non-maintained fittings suit workplaces like offices where occupants know the building and normal lighting illuminates escape routes. Your fire risk assessment should determine the appropriate type.
BS 5266-1 requires monthly functional tests and annual full-duration tests. Monthly tests briefly activate fittings to confirm operation. Annual tests run systems on battery for the full rated duration, typically three hours. Results must be recorded in a logbook.
The 2025 revision expanded scope to cover local area lighting and standby lighting alongside emergency escape lighting. It aligns with updated European standards EN 1838 and EN 50172, and provides clearer guidance for modern building safety needs.
299 Lighting offers full emergency lighting design support, including spacing calculations, photometric data, and compliance documentation. Our LIA-accredited engineers can review your scheme and prepare technical submissions to demonstrate compliance with British Standards.
For spaces where aesthetics matter, 299 Lighting supplies integrated emergency options for downlights, linear luminaires, and suspended fittings. These allow emergency lighting to blend with your general lighting scheme rather than requiring separate, visible emergency fittings.