A public address or PA system is a combination of a set of audio equipment that allows broadcasts over a designated area. Often found in schools and office buildings, PA systems can be used for announcements or emergency information and provide a simple way to get information out quickly. PA systems can be basic or advanced, and can be adapted to fit a variety of needs. It is a centralized amplifier based system that’s been designed to provide voice paging and to broadcast alarm tone during emergencies. The system can transmit alarm tone and routine voice messages, from a central location, to all or selected areas of the facility, in a reliable and safe manner, by the use of loudspeakers. The entire operational area / facility can be divided into one or more zones, which can be accessed independently either for announcements or for alarm broadcasting. The loudspeakers are installed in these zones. There are no limitations to number of zones in the system or number of loudspeakers in each zone. Each loudspeaker is connected to the central equipment for amplification and other control functions. Depending on the surrounding environment, either flameproof loudspeakers (for hazardous atmospheres) or weatherproof loudspeakers (for safe & non-hazardous atmospheres) or indoor loudspeakers (for indoor areas) are installed in each zone. The loudspeakers are available in different wattage, sizes, types and constructions. The system is designed to offer clear reproduction of sound and intelligibility of speech even in high noisy areas. The system uses high reliability amplifiers with built in over load protection circuitry, short circuit protection, open circuit protection and thermal protection.