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Lighting Guides

A step by step guide Probably your first thought on seeing this article was, ‘why a whole lighting guide just for stairs?’ Good point, and I should say it did start out as just a Factfile. This was needed because we realised that Standard BS EN 12464, while giving recommended lighting levels for various types of stairs, didn’t say where these levels were to be calculated or measured. This, of course, applied equally to our own Code for Lighting as it used the identical levels from the standards. The problem was that every time I presented a draft Factfile to the technical publications committee, someone would say ‘yes, but what about ramps?’, ‘…refuge areas?’, ‘…emergency lighting?’, ‘…escalators?’ and so on. So, we now have a 20-page Lighting Guide on lighting for stairs full of recommendations for safe locations for luminaires, positioning to allow safe access for maintenance, exit signage locations and, of course, where to calculate and measure lighting levels on the staircases. In most buildings there are two types of stairway: those used constantly by the occupants to pass up and down the building, normally referred to as accommodation stairs, and the escape stairs that are rarely used except to evacuate the building. The main or accommodation stairways can vary from being simply decorated and lit, as in a typical hospital or factory, to more lavishly decorated and feature lit in some more upmarket shops, offices and hotels. The escape stairs are often left undecorated and lit in a very functional and simple way. Both sorts of staircase will need an emergency lighting system to provide illumination in the event of a failure of the normal power supply. This emergency lighting system prevents falls when the main lighting goes off, and is there to provide lighting to the stairs and landings to enable safe evacuation of people from the building if needed. Lights are often positioned at each landing, as this ensures that the top and bottom of the flights of steps are easily lit. The landing also provides a flat platform to erect step-ladders or other access equipment for cleaning and maintenance. The average maintained lighting level on the main landings should be the same as the recommended lighting level for the stairway – the normal criteria for uniformity apply. In general, the lighting should be as even as possible with no sharp changes of light level. No shadows should occur across the landings, as this may be misinterpreted as a step. It is important to light well small quarter landings where a stair turns so that users can accurately judge the stop of one flight and the start of the next. It is also important to light well any ‘rest’ landings that are used to break up long continuous flights

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Photography: Corrado Serra

Paul Ruffles outlines the society’s new LG16 which focuses on lighting stairways – from the strictly functional to flights of fancy

DPA Lighting worked with Eva Jiricna Architects to light the Tiffany Gallery at the redesigned Luce Center at the New-York Historical Society Museum and Library. The centrepiece staircase is lit with cool-white, integrated linear LED fittings

into shorter sections. This ensures that users can see that what might appear to be one very long flight suddenly has a much wider ‘step’, that is in fact a landing, to allow users to pause safely if they cannot make the whole long flight in one go. Luminaires must not be positioned such that they reduce the width of the stairs, as this might infringe local building regulations on minimum widths. They should also not be placed in locations where they could be hit by the body or head of those passing up or down the stair or crossing landings. If at all possible, they should not be positioned above the stair flights themselves, as access for maintenance is difficult and access equipment may compromise the use of the stairs. Luminaires should also not be positioned on landings directly above doors that open on to the landing, as there is a risk of impact on any access equipment being used, and again such equipment may impede people’s escape. Refuge areas, where wheelchair users and those with

Profile for Matrix Print Consultants Ltd

SLL July/August 2017  

SLL July/August 2017