The British fire consortium have recentlly issued guidance on ISO16069 and low location lighting systems. The leaflet is reproduced on the safelincs site.
http://www.safelincs.co.uk/page.php?xPage=bfc2.htmThe leaflet seems to infer that LLL is a requirement in all buildings.
"""It is clear that LLL systems are essential and are to be considered as primary signage along with the high level system. These signs, like those in system 1, are designed to mark the evacuation routes, the exit doors and first aid fire fighting equipment......Because it is designed to be used in situations of low visibility where smoke is present and where people will stoop or crawl, the top of LLL signs must be fixed at 40cm from floor level, allowing people to follow the system whilst in these positions. """"
Is this the correct interpretation? In all buildings? To plan for persons having to crawl in smoke would appear to me to be expecting a failure of the passive, active and management proceures in the building and therefore in contradiction of the Prnciples of Prevention.
I agree that low level lighting and signage may be a suitable risk control measure in some situations - cinemas, theatres, aircraft, ships, where there is a combination of other risk factors.
Do we know what the original intention of the ISO was?