"Fire alarm systems" as "Any manually operated system designed to give warning of fire".Normally, this system consists of break glass units (manual call points), alarm bells, and electrical /electronic fire control panels wired together, such that when a break glass unit is actuated, the alarm bells of the entire building will sound, unless the system is silenced manually at the fire control panel. Look at this link for some installations.

In very tall buildings in Hong Kong, the sounding of the bells may be limited to the fire floor, 2 floors above it, and one floor below it, to prevent evacuation of people to occur at the same time. Other automatic fire detectors such as smoke / heat detectors and / or sprinkler flow detector, may be connected and to the same fire control panel with the manual fire defection system using the break glass units, and to sound the same set of bells.

The control panel is normally housed in a Fire Control Centre, or in a prominent position nearby the firemen's lift access, and / or the location of the building guard.

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