The LWF Blog

Fire Safety for Facilities Management Personnel – Emergency Wayfinding Systems – Part 174

October 31, 2022 12:44 pm

Lawrence Webster Forrest (LWF) is a specialist fire engineering and fire risk management consultancy whose aim is to give information on best practice in fire safety for facilities management personnel through this blog series. In part 173, LWF looked at what checks should be undertaken annually to ensure the proper maintenance of an emergency escape lighting system (daily and monthly inspections having been detailed in part 172 of this series). In part 174, we will discuss emergency wayfinding systems and directional sounders.

Emergency wayfinding systems are separate to any emergency lighting provision designed to operate when the main power system fails. An emergency wayfinding system is based on tracks of light installed at a low level along the edges of the route and around exit doors to assist building occupants when they are evacuating.

The tracks are likely to be visible when smoke is in the escape route, particularly so because smoke rises due to the heat and the tracks are installed at a low level.

There are four main types of emergency wayfinding system available:

• Electroluminescent systems
• Miniature incandescent systems
• Light-emitting diode (LED) systems
• Photo luminescent systems

The first three systems require a source of power, which, as emergency wayfinding systems are designed to work when other mains-based electricity has failed, will be battery-based.

The fourth type of system – photo luminescent – works after previous exposure to artificial light. While the premise of a system that can work independently of an outside power source is very useful, research undertaken by the Building Research Establishment (BRE) has concluded that photo-luminescent systems do not produce enough light for visually impaired people to see.

Photo-luminescent systems are commonly seen on aircraft, highlighting the passageway between seats to assist passengers in low-visibility conditions.

Directional Sounders

Directional sounders are a rarely-seen audible wayfinding system. They may be used to assist people in finding their way to fire exits. Directional sounders are effective in helping people to follow an escape route in buildings, ships and aircraft. Given that they are auditory assistance, they are particularly useful for blind or partially-sighted people when evacuating.

They are also designed for use when vision may be obstructed by smoke, but there is certainly an argument that no escape route should be obstructed by thick smoke at the evacuation stage of a fire.

In part 175 of this series, LWF will continue talking about directional sounders before beginning to look at fire safety signage. In the meantime, if you have any queries about your own facilities or wish to discuss this blog series, please contact LWF on freephone 0800 410 1130.

Lawrence Webster Forrest is a fire engineering consultancy based in Surrey with over 35 years’ experience, which provides a wide range of consultancy services to professionals involved in the design, development and construction and operation of buildings.

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.