The LWF Blog

Fire Safety Engineering for Design – Siting of Escape Lighting – Part 179

April 15, 2024 11:09 am

LWF’s Fire Safety Engineering blog series is written for Architects, building designers and others in the construction industry to highlight and promote discussion on all topics around fire engineering. In part 178, LWF looked at the principal documents covering emergency lighting in the UK, before discussing additional escape lighting. In part 179, we will talk about high-risk task areas and open plan and undefined areas of a building in the context of emergency lighting.

Any area within a building, where a high-risk task is undertaken should be allocated emergency lighting. For instance, an area such as a plant room, lift motor room, electrical switch rooms and any area where a safety hazard is present should have backup emergency lighting installed. Not only may such areas need to be used by persons during the mains power outage, but they could become dangerous for anyone moving about in darkness.

Open-plan and undefined areas

In BS EN 1838 the use of emergency lighting in open and undefined spaces is referred to as ‘anti panic’. It is provided because often in such areas, the escape routes are not immediately obvious and furniture may be placed in a way that could hinder safe egress from the area in darkness. BS 5266-1 offers examples of open-plan areas that may need emergency lighting following a suitable risk assessment.

In England, the Building Regulations 2010 contain recommendations that an area over 60 m2 be provided with emergency lighting. This may include areas such as undefined escape routes, where the occupants of a space may take several different routes to the nearest exit.

BS 5266-1 recommends the minimum illumination level for such areas and situations to be 0.5 lux in the core area. This level of lighting is the minimum level and therefore consultation with the building owners and other relevant parties should be undertaken to ascertain how the level of illumination might affect the users of the building and if it should be adjusted accordingly.

The National Fire Prevention Association (NFPA) and International Building Code (IBC) do not take this approach to open-plan areas. In these codes, there is no requirement to have overall illumination in an open plan area, but rather to illuminate only those areas classified as escape routes. An assessment should be made of what areas of an open-plan area should be classified as an escape route, but they are generally guided by the furniture layout and the areas most likely to be used as egress routes by the occupants.


In part 180 of LWF’s series on fire engineering we will look at the illumination of exit signs. In the meantime, if you have any questions about this blog, or wish to discuss your own project with one of our fire engineers, please contact us.

Lawrence Webster Forrest has been working with their clients since 1986 to produce innovative and exciting building projects. If you would like further information on how LWF and fire strategies could assist you, please contact the LWF office on 0800 410 1130.

While care has been taken to ensure that information contained in LWF’s publications is true and correct at the time of publication, changes in circumstances after the time of publication may impact on the accuracy of this information.

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