| 摘要 |
<p>An intrinsically safe emergency light and sound system comprising an impact resistant IP54 rated steel enclosure in which high intensity light emitting diodes are housed (13) together with a speaker (16). Their operation is controlled by a printed circuit board (14) and can be powered by an internal rechargeable battery (15). Enclosures are grouped in sets of three at intervals of five metres and connected by intrinsically safe heavy duty cable (11), and each set is located at intervals of between twenty and forty metres. When an incident or an explosion occurs causing smoke and dust the system can be activated by a switch signal to a remote trigger board. Alternatively when mains power is switched off the system will be activated, and sequentially flashing lights and audible tones set at a different pitch between sets will commence to operate. The system directs those who suffer reduced visibility and disorientation, due to smoke and dust, towards the safest direction of egress. Due to independence and severability of each set in the system, damage or removal of any one set will not disable the other sets from operating.</p> |
