System components of an evacuation system
An evacuation system consists of a number of system components. Roughly you can divide the evacuation system in the central, speakers and other signaling devices.
‘’The central is the beating heart of an evacuation system’’
There are several manufacturers and these manufacturers develop different centrals and then each manufacturers also has its unique arguments. Basically, the system are generally all the same.
The basis of a modern central is the logic part. This part communicates with other systems, regulates the internal controls and is responsible for the internal protection. The latter is very important because that is just the difference between a public address system and evacuation system.
The regulation of a central is usually performed through the control panel.
The evacuation central includes an output section that consists of audio amplifiers and switching logic to control the right speakers. The minimum requirements are recorded in a product standard and an evacuation central must comply with the requirements. This is tested during a type test.
The speakers are usually mounted in the ceiling or on the wall. The speakers are divided into groups, called zones. Usually the area defining of the evacuation is similar to the fire panel. Speakers for evacuation systems have a high protection for flames, because they should continue to work as long as possible during a calamity. Of course the speakers will stop working at some moment, but not that easily.
The minimum requirements are recorded in a product standard and a speaker for evacuation purposes must comply with these requirements. This is also tested during a type test. The speaker is connected via a cable to the central. These cables also need to comply with the necessary requirements.
Besides speakers there are also other types of signaling devices used, such as light panels and even vibrating panels. The light panels are often used in a noisy environment. Vibrating panels are used for people with a hearing impairment. However, there are no product standards for this signaling devices.