AUST – HENDRY building surveyors advises that building owners, occupiers and certifiers who are either considering increasing an occupancy level under the Building Regulations in a building beyond normal allowable limits (pursuant to an approval situation), or who need to justify increasing exit travel distances, should consider (as part of a fire engineered alternative solution), under the Building Code of Australia (BCA) the merits of a unique sounder device that emits distinct sound to alert and lead occupants in the building to an exit during an evacuation.
The product development through travel notifier/Inertia by Honeywell is an extension to a building occupant warning system and is activated by the fire panel that is part of the building fire alarm system for evacuation. Installation could be via an emergency plan under AS3745 – 2010 planning for emergencies in facilities.
The device is located at all exit points, in paths of travel to an exit and within an exit and overcomes recognition problems experienced by building occupants in identifying the location of an exit particularly when smoke density has obscured exit signs and other visual cues during an evacuation.
The directional sound that is emitted, of which there are seven different patterns, can be heard by a person over and above other emergency sounders. The sound output is set at 15dB(A) above background noise. Testing shows that significant delays caused by the difficulty for occupants to find an exit during an evacuation and then exit the building can be avoided because of the effective guidance provided by the device.
The product does not replace occupant warning systems but compliments these systems as well as emergency lighting and exit signage etc installed in a building. According to the manufacturer, the reduction in the evacuation time taken by occupants can be by at least 30%, depending on circumstances.
This means that time lost because of way finding and queuing at inappropriate doors could be reduced thus allowing occupants to evacuate a building quicker resulting in the potential to increase population above normally accepted circumstances or for extended travel distances to be more readily accepted. This could only be the case if it is shown that tenability can be sustained during evacuation and is proven to be the case by fire engineering analysis via an alternative solution process under the BCA.