Manual Alarm Call Points

The positions of fire alarm call points should be indicated with this type of sign particularly in areas where it may be necessary to identify the location of a manual alarm call point from some distance, e.g. in a large warehouse. 

Manual Alarm Call Points (MACs) allow an operator to initiate the emergency response system, regardless of the response of the automatic instrumentation. They can be used for any type of emergency. The typical MAC is of the open contact Break Glass type, suitable for Division 1 locations. MACs should be covered with a guard to prevent inadvertent alarm activation. They should be clearly visible and labeled and easily operable by personnel wearing personal protective equipment (PPE) such as gloves. 

Manual alarm call points Does not rely on instrumentation Likely to be slow False alarms possible Outdoors and at key locations indoors... 

Manually operated alarm call points should be provided ih all parts of a building where people may be present, and should be located so that no one need walk for more than 30 m from any position within the premises in order to give an alarm. 

Manually operated alarm call points should be provided in all parts of a building where people may be present, and should be located so that no one need walk for more than 30 m firom any position within the premises in order to give an alarm. A breakglass manual call point is shown in Fig. 14.49. They should be located on exit routes and, in particular, on the floor landings of staircases and exits to the street. They should be fixed at a height of 1.4 m above the floor at easily accessible, well illuminated and conspicuous positions. 

The location of extinguishers >- The location of manual fire alarm call points >- The location of evacuation assembly points >- Fire action signage. 

The location of manually operated fire alarm call points and control equipment for the fire alarm... 

All of these are very well visualized in cause and effect diagram which is presented in a tabular matrix form. Normally, various causes such as manual call point, heat (say) rate of rise, flame detection (say) infrared, etc., whereas effect gives the details like audible alarm, audio visual alarm in DCS, etc. Generally these documents need approval (from competent authority). 

In a large proportion of buildings a simple evacuation strategy will be adopted and on the operation of a manual call point or detection by an automatic fire detector, fire alarm sounders will provide warning and indicate the need for a full evacuation of the building. 

Zones - to support the above arrangements the building will need to be divided into a number of alarm zones in such a way that the fire alarm sounders reflect an operation of a manual call point within that area or a detector. 

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