Owners of multi-tenant office buildings have a number of fire alarm design
options today - thanks to technology advances. Systems can be installed to meet
occupancy requirements for common areas, as well as provide the backbone of
an expandable system installed as tenant spaces are built-out. After ensuring
that all local code concerns are understood and provided for, the system planner
and building owner have decisions to make. The local competitive market for
space may determine one that deals with cost sharing for the fire alarm system.
The sharable costs are derived from the type of system chosen and the portion
of the cost allocated to the tenant. In a competitive space market, a systems
approach that reduces a prospective tenant's cost without negatively affecting
the building owner's budget may be the appropriate action to take.
One approach that fits the goal of providing a tenant-friendly fire alarm system
in many small- to medium-sized buildings is to install an intelligent addressable
expandable fire alarm control panel. Activate a Signaling Line Circuit (SLC)
to monitor devices in common areas and control fans and elevator recall functions.
Be sure the panel selected has expansion capability to handle the needs of each
tenant area. Fire alarm panels are available that can accommodate 2,000-plus
input/output devices. Depending on floor sizes, this can be accomplished by
either assigning one SLC per floor or multiple floors. Since each device connected
to a SLC is individually addressed, its display and outputs can be tied to the
requirements of the tenant's floor, allowing a single SLC to be applied to multiple
floors. However, this approach carries the potential limit created by the number
of devices input and output each SLC is capable of supporting. The number of
devices per SLC varies by manufacturer and may be further limited by the mix
of input vs. output devices. This approach works best in new installations and
is also successful in retrofit applications if the equipment selected can use
existing wiring.
A second approach is installing a network system where each tenant has a dedicated
fire alarm control system for its area. This approach can be more expensive
and is more suitable for larger buildings and multiple-building applications.
With the additional investment, it does provide for maximum expansion capability
that is limited only by the size of the individual panels.
Another consideration is the type of local notification devices required as
part of the system. The most common are horns with strobes used to alert occupants
of a fire emergency. A second means of notification is emergency voice evacuation
systems. Both types can be applied to a backbone system approach. The advent
of notification appliance circuit expanders with built-in horn/strobe synchronization
drivers for maximum design flexibility and distributed audio panels makes this
possible. The use of expanders also facilitates the meeting of ADA requirements.
The careful review of the capabilities of prospective fire alarm systems, coupled with an understanding of local codes and requirements, will ensure that both current and potential future needs of a building owner and each tenant can be accommodated in a cost-effective manner. A flexible main fire alarm control panel and system design will make the process of adapting to changes in either tenants or code requirements less challenging.
Ken Beeson is vice president of marketing at The Gamewell Co. (www.gamewell.com),
Ashland, MA.
