A ZigBee network application in emergency exit guiding

The emergency exit lights are important devices for fire alarm fighting. Most of the emergency exit lights are illuminated for 24 hours and then waste much energies. This paper proposed a wireless alarm system with multi-functional power-saving emergency exit indicating lights. A ZigBee network is constructed for the alarm system. The gas and the smoke sensors are used to report the emergency events in the system. A human body infrared sensor is mounted on the emergency exit indicating light. When the alarm system is operated in the normal mode, the emergency exit indicating lights illuminate at a low lighting level if there are nobody nearby. The lighting level is raised to high as an assistant illumination if somebody entered the infrared sense region. When an emergency state is reported by the sensors, the alarm system is switched into the emergency mode. All the emergency exit indicating lights are flashed synchronously in the emergency mode in order to distinguish from the normal illumination lights. The synchronously flashed emergency exit lights are helpful to identify the direction for people to escape from the danger spot.