Emergency Lighting Design and Installation: BS 5266 Requirements Explained

Getting emergency lighting right starts at the design stage. A system that is poorly designed will never be fully compliant, no matter how well it is tested or maintained. Yet many commercial buildings across Manchester have emergency lighting that was installed without a proper design — luminaires placed where it seemed convenient rather than where BS 5266-1 actually requires them.

BS 5266-1:2016 is the British Standard that sets out the code of practice for the emergency lighting of premises. It covers everything from where to position luminaires to the minimum light levels required on escape routes. If you are planning a new installation, upgrading an existing system, or simply trying to understand what your building needs, this guide explains the key emergency lighting design requirements in plain English.

Why Design Matters

Emergency lighting is not simply about fitting a few battery-backed luminaires above the doors and hoping for the best. The purpose of the system is to provide sufficient illumination to allow safe evacuation of a building when the normal lighting fails. That means every escape route, every change of direction, every stairway and every exit must be adequately lit — and the only way to achieve this is through proper design.

A well-designed emergency lighting system:

Ensures all occupants can identify and follow escape routes
Illuminates safety signs, fire-fighting equipment and call points
Provides anti-panic lighting in large open areas
Meets the minimum light levels and uniformity ratios required by BS 5266-1
Minimises dark spots and shadows that could cause trips, falls or disorientation
Accounts for the specific layout and use of the building

A poorly designed system may leave critical areas in darkness, creating a serious safety risk and leaving the building owner exposed to legal action.

Key BS 5266-1 Design Requirements

Escape Route Lighting

Escape route lighting is the core requirement for most commercial buildings. BS 5266-1 specifies the following minimum standards for escape routes:

Minimum illuminance: 1 lux along the centre line of the escape route, measured at floor level
Uniformity ratio: The ratio of maximum to minimum illuminance must not exceed 40:1 along the centre line
50% within 5 seconds: The system must provide at least 50 per cent of the required illuminance within 5 seconds of a mains failure
Full illuminance within 60 seconds: The full 1 lux must be achieved within 60 seconds
Mounting height: Luminaires should generally be mounted at least 2 metres above floor level

These requirements apply to all defined escape routes within the building, including corridors, passageways, stairways and the areas immediately outside final exits.

Where Luminaires Must Be Positioned

BS 5266-1 requires emergency luminaires to be positioned at the following locations (as a minimum):

1. At each exit door — to illuminate the door and any steps or level changes immediately beyond it 2. Near stairs — so that each flight of stairs receives direct light, with a luminaire at the top and bottom of each stairway 3. At each change of direction — where the escape route turns, intersects with another route, or changes level 4. At each intersection of corridors — where occupants must make a decision about which direction to take 5. Outside and near each final exit — to illuminate the area immediately outside the building to a point of safety 6. Near each fire alarm call point — so that the call point can be located and operated in the dark 7. Near each piece of fire-fighting equipment — including fire extinguishers, fire blankets and hose reels 8. Near each first aid point — where first aid equipment is provided 9. At each change of floor level — including ramps, steps and any variation in floor level along an escape route 10. Near accessible toilet facilities — toilets larger than 8 square metres, or any toilet specifically designed for disabled users, require emergency lighting 11. In lift cars — to provide illumination if the lift becomes trapped between floors during a power failure 12. In motor generator, control and plant rooms — areas containing critical building services that may need to be accessed during an emergency 13. Near covered car parks — the escape routes from covered car parks require emergency lighting

Anti-Panic Area Lighting

For open areas larger than 60 square metres (such as open-plan offices, warehouses, retail floors, conference halls and assembly areas), BS 5266-1 requires anti-panic area lighting in addition to escape route lighting. The requirements are:

Minimum illuminance: 0.5 lux across the entire area, measured at floor level (excluding a 0.5-metre border band around the perimeter)
Uniformity ratio: Maximum to minimum ratio must not exceed 40:1
Purpose: To reduce the risk of panic and allow occupants to reach a defined escape route safely

Anti-panic lighting is particularly relevant for the large converted warehouse and mill spaces found across Manchester, which are increasingly used as offices, event spaces and co-working facilities.

High-Risk Task Area Lighting

In areas where a sudden loss of light could create an immediate danger — for example, near moving machinery, chemical processes or where people are working at height — high-risk task area lighting is required. The requirements are:

Minimum illuminance: 10 per cent of the normal task illuminance, or 15 lux, whichever is greater
Full illuminance within 0.5 seconds: The system must reach the required level almost instantly
Purpose: To allow workers to shut down dangerous processes safely

This requirement applies primarily to industrial and manufacturing premises, but can also be relevant in commercial kitchens, workshops and laboratories.

Duration Requirements

The duration for which emergency lighting must operate depends on the type of premises:

| Premises Type | Minimum Duration | |---|---| | Most commercial buildings (offices, shops, restaurants) | 1 hour | | Sleeping accommodation (hotels, care homes, residential buildings) | 3 hours | | Entertainment venues and places of assembly | 3 hours (recommended) | | High-risk task areas | Duration of the hazard |

The duration is measured from the point of mains failure. The system must maintain the required lux levels throughout the entire duration period — a luminaire that provides adequate light for 45 minutes but then dims below 1 lux has failed the test.

Luminaire Types and Selection

Several types of emergency luminaire are available, and the choice depends on the application:

Self-Contained Luminaires

Each unit contains its own battery, charger, lamp and control gear. These are the most common type in smaller to medium-sized commercial buildings.

Maintained — the lamp operates continuously as part of the normal lighting and switches to battery power during a mains failure. Used where the luminaire also provides normal illumination (common in corridors and stairways).
Non-maintained — the lamp only illuminates during a mains failure. Used where separate normal lighting is provided and the emergency luminaire serves solely as a backup.
Sustained — contains two lamps: one for normal use and one for emergency use. The emergency lamp activates only during a mains failure.

Central Battery Systems

A single battery bank (or pair of banks for redundancy) supplies power to multiple luminaires via dedicated wiring. These are more common in larger commercial buildings and offer advantages in terms of centralised maintenance and monitoring.

LED vs Fluorescent

Modern LED emergency luminaires offer significant advantages over older fluorescent types:

Lower power consumption — longer battery life or smaller batteries required
Longer lamp life — 50,000+ hours versus 8,000–15,000 for fluorescent
Instant start — no warm-up period, which is critical for meeting the 5-second and 0.5-second requirements
More compact — smaller luminaires that are easier to integrate into modern interiors
Reduced maintenance — fewer lamp replacements over the system lifetime

For new installations and upgrades, LED is now the default choice.

Installation Best Practice

Circuit Separation

BS 5266-1 requires that the wiring for emergency lighting is separated from normal lighting circuits. This ensures that a fault on the normal lighting circuit does not also disable the emergency lighting. In practice, this means:

Emergency lighting should be on its own dedicated circuit(s)
Cables for emergency lighting should be routed separately from normal lighting cables where practical
In buildings with fire alarm systems, the emergency lighting wiring should be fire-rated (to BS 8519 or BS 7629) if it passes through areas that could be affected by fire

Commissioning

Every new emergency lighting installation must be commissioned in accordance with BS 5266-1. Commissioning includes:

Verification that the system has been installed in accordance with the design
Measurement of illuminance levels on escape routes and in anti-panic areas
Functional testing of all luminaires
A full-duration test after the initial 24-hour charging period
Issue of commissioning documentation and as-built drawings

Certification

The installing contractor should provide:

An electrical installation certificate (BS 7671)
A commissioning certificate (BS 5266-1)
As-built drawings showing luminaire positions
A logbook for ongoing testing and maintenance records
Operating and maintenance instructions for the system

Common Design Mistakes to Avoid

1. Relying on normal lighting design software — emergency lighting design requires specialist calculation tools that account for battery-powered light output, which is lower than mains-powered output 2. Spacing luminaires too far apart — this creates dark spots between units and fails the uniformity requirement 3. Ignoring changes of direction — every turn, junction and intersection needs a luminaire, even if the corridor is short 4. Forgetting external areas — the escape route does not end at the door; the area immediately outside the final exit must also be illuminated 5. Not accounting for building changes — partitions, new rooms and altered layouts can invalidate the original design 6. Specifying non-maintained units in areas that need maintained — stairways and corridors that rely on emergency lighting as their only source during normal use must have maintained or sustained luminaires

Manchester and Greater Manchester Context

Commercial buildings across Greater Manchester present specific design challenges:

Listed buildings in Manchester city centre may have restrictions on luminaire placement and containment routes
Multi-tenancy buildings require careful coordination between tenants and the building owner to ensure continuous coverage of shared escape routes
Basement and sub-basement premises (common in Manchester's commercial core) have no natural daylight and require robust emergency lighting that can operate for the full duration
High-rise commercial buildings around Deansgate and Spinningfields require emergency lighting on every floor, in every stairway and in all lobbies — a significant design exercise
Building control teams across Manchester, Salford, Stockport, Tameside and Rochdale all reference BS 5266-1 when reviewing emergency lighting submissions for new developments and refurbishments

Get a Professional Emergency Lighting Design

Whether you need a new emergency lighting installation, an upgrade to your existing system, or a design review to check compliance, Manchester Compliance can help.

Contact us today:

Phone: 0161 706 0244 (Monday–Friday, 8:00 AM – 5:00 PM)
Email: hello@manchestercompliance.co.uk
Address: 25 Holden Clough Drive, Ashton-under-Lyne, OL7 9TH

Our emergency lighting designs are carried out to BS 5266-1 by experienced, NICEIC-certified electricians. We provide full design documentation, installation, commissioning and ongoing maintenance — everything you need for complete compliance.

Emergency Lighting Design and Installation: BS 5266 Requirements Explained