Plan Review for a Fire Alarm System in a Historic Building
A fire alarm system is being installed in a historic building that is being renovated into a museum. The building has ornate plaster ceilings, wood paneling, and limited space for wiring. The design team has submitted plans for a conventional fire alarm system with manual pull stations and heat detectors in the museum galleries, and smoke detectors in the mechanical rooms and storage areas. The building is three stories with a basement. The plans show notification appliances in the corridors and public areas, but not in the galleries because the ceiling height is 18 feet and the architect wants to preserve the aesthetics. The fire code official must review the plans for compliance with NFPA 72 and the Alaska Fire Code. The building has a sprinkler system but it is not monitored by the fire alarm system. The plans do not include a battery calculation or a sequence of operations.
1. What are the major deficiencies in the submitted plans according to NFPA 72 and the Alaska Fire Code?
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Major deficiencies include: 1) Notification appliances are not shown in the museum galleries, which are public areas; NFPA 72 requires visible and audible notification in public areas unless an exception applies. The high ceiling may require special consideration for visible appliances. 2) The sprinkler system is not monitored by the fire alarm system; NFPA 72 requires that sprinkler waterflow and supervisory signals be monitored. 3) The plans lack a battery calculation; NFPA 72 requires that the battery be sized to support the system for 24 hours standby plus 5 minutes alarm. 4) The plans lack a sequence of operations; NFPA 72 requires a written sequence of operations to describe the system's response to alarm, supervisory, and trouble signals. 5) The use of heat detectors in galleries may not provide adequate life safety protection; smoke detection may be required depending on the occupancy and combustibles. 6) The plans must show the location of the fire alarm control unit and remote annunciators. 7) The Alaska Fire Code may have additional requirements for historic buildings, such as preservation of aesthetics, but life safety takes precedence. The fire code official should require the plans to be revised to address these issues.
2. How should the fire code official address the architect's concern about aesthetics in the galleries?
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The fire code official should explain that life safety requirements cannot be compromised for aesthetics. However, there may be alternative solutions that satisfy both. For example, the use of small, unobtrusive notification appliances that blend with the decor, or the use of voice communication systems that can provide both audible and visible signals. The code official can also consider performance-based design alternatives if they provide equivalent safety. The official should require that the notification appliances be installed in accordance with NFPA 72, which may include mounting them on the walls or ceilings in a way that minimizes visual impact. If the ceiling height is 18 feet, visible appliances may need to be placed at a lower height or use special lenses to ensure visibility. The official should not waive the requirement without a documented equivalent level of safety. The architect should be encouraged to work with the fire alarm designer to find compliant solutions.