Fire protection strategies are designed and installed
to perform specific functions. For example, a fire sprinkler
system is expected to control or extinguish fires. To accomplish
this, the system sprinklers must open, and the required amount
of water to achieve control or extinguishment must be delivered
to the tire location.
A fire detection system is intended to
provide sufficient early warning of a fire for occupant
notification and escape, fire service notification, and in some
cases activation of other fire protection features (e.g.,
special extinguishing systems, smoke management systems). Both
system activation (detection) and notification (alarm) must
occur to achieve early warning.
Construction compartmentation is generally designed to
limit the extent of fire spread as well as to maintain the
building's structural integrity as well as tenability along
escape routes for some specified period of time. In order to
accomplish this, the construction features must be fire
"rated" (based on standard tests) and the
integrity of the features maintained. The reliability of
individual fire protection strategies such as detection,
automatic suppression, and construction compartmentation is
important input to detailed engineering analyses associated
with performance based design. In the context of safety
systems, there are several elements of reliability,
including both operational and performance reliability.
Operational reliability provides a measure of the
probability that a fire protection system will operate as
intended when needed. Performance reliability is a measure
of the adequacy of the feature to successfully perform its
intended function under specific fire exposure conditions.
The former is a measure of component or system operability
while the latter is a measure of the adequacy of the system
design. The scope of this study was limited to evaluation of
operational reliability due primarily to the form of the
reported data in the literature. In addition to this
distinction between operational and performance reliability,
the scope focused on unconditional estimates of reliability
and failure estimates in terms of fail-dangerous outcomes.
A discussion of these terms is provided later in the paper.
This paper provides a review of reported operational
reliability and performance estimates for (1) fire
detection, (2) automatic suppression, and to a limited
extent (3) construction compartmentation.
In general, the reported estimates for tire detection are
largely for smoke detection/fire alarm systems; automatic
sprinklers comprise most of the data for automatic
suppression, and compartmentation includes compartment fire
resistance and enclosure integrity. It should be noted that
in some cases the literature did not delineate beyond the
general categories of "fire detection" or
"automatic suppression," requiring assumptions
regarding the specific type of fire protection system.
Fire precautions are all the measures aimed to reduce
damages following from a fire.
Interventions are subdivided in active or passive precaution
measures in relation to the intervention of an operator or
the starting of a device as needed.
All precaution measures requiring an operator or the
starting of a device are necessary to realize a fire in a
short time, to signal and put it out by:
fire prevention systems
fire barrier doors