Fire Protection Design Manual - Office of Construction and Facilities ...

September-2011
For Example: (tone alert) “Code Red, First Floor Center, Code Red, First Floor Center,
Code Red, First Floor Center.” The message content is to be coordinated with the local VA
Medical Center Staff.
g. Manual operation of the voice system will override all automatic voice messages in
the system.
Why do it this way?
The operation provided above will elicit a more rapid response from staff in the zone of
alarm origin since this is the only location where visible strobes and the temporal three
signal are activated. The strobes and temporal three signals require no interpretation and
staff can immediately respond. In older coded systems and in voice systems, the
occupants/staff must take time to interpret what the code is or what the voice message says
before carrying out their defined duties in a fire event.
Since most health care buildings in the VA are actually mixed occupancies, the arrangement
above works well for those buildings that contain mixed occupancies. If the alarm originates
in an area (this could be an entire floor) of a health care building that is a business
occupancy or equivalent, the alarm system would generate a temporal three signal and
activate the visible appliances throughout the area. This would be the proper signal for
untrained occupants to evacuate. If there are staff in the area, they will be trained to take
appropriate action for the signal received.
Other Issues
h. To help ensure that the alarm is initiated in the zone of alarm origin, smoke detectors
that are installed to hold open smoke barrier doors at smoke zone barriers shall be
installed on both sides even though NFPA 72 allows, in some cases, a detector to be
installed on one side only. Detectors shall then be programmed for their respective
zone to initiate the proper alarm as well as to close the door served.
Note: It should be noted, and it is recognized, that there is always a possibility that the
smoke from a fire would set off a detector in an adjacent zone first, or a staff member may
activate a manual box in an adjacent zone.
There are other systems that can be utilized to help summon staff during a fire alarm
activation. These include paging and radio systems. In some instances it may be beneficial
to tie the fire alarm system outputs to summon staff by way of these systems.
i. While fire alarm voice communication systems are not permitted to be used as
general paging systems, they may be used for emergency communications other than
fire emergencies where the operators are trained in the use of the system.
General Requirements
j. Provide speakers to be heard in all locations throughout the protected premises from
where staff must respond. This may include more than one building if the number of
staff within a building is not adequate. For health care, nursing ward areas should be
utilized for responders since areas other than nursing wards (e.g., administration
areas) will generally be occupied only during normal business hours.
k. Speakers shall be installed and arranged so they are clearly heard and understood by
staff under normal working conditions. A rule of thumb for speaker layout is to
install them every twenty-five to thirty feet on center and not to expect them to be
clearly heard through more than one wall.
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