Operation
P/N 06-237041-001 4-21 February 2011
4-10.6.1.2 Occupant Notification/Building-Evacuation Alarm Events
An occupant-notification/building-evacuation system is usually installed as required by fire codes to
warn the occupants of a building to evacuate because of a fire. This system enters the alarm state
when devices such as an automatic detector, a manual-alarm station, or a waterflow switch reports
as an alarm event. The FenwalNET 8000-ML system uses temporal-coded horns and strobes (or
other method of non-voice-messaging, public notification acceptable to the authority having
jurisdiction) to notify the occupants to evacuate the building.
An occupant-notification/building-evacuation system has two sub-alarm states that are designed to
delay the building-evacuation signals or to prevent a transient, non-fire signature from activating the
building-evacuation signals. These two sub-alarm states are Positive-Alarm Sequence and Alarm
Verification, described previously.
Table 4-5. Progressive Alarm States of a FenwalNET 8000-ML System
State When Occurs
Pre-Alarm State The pre-alarm state occurs when any automatic detector that is a member of a crossed-zoned or
counting-zone detection system issues an alarm report. The pre-alarm state for a property-protection/
mission-continuity system with waterless fire suppression typically refers to the receipt of an alarm
signal from a spot-type smoke detector or an HSSD. The pre-alarm state described in
Paragraph 4-10.5 dealt with essentially a warning signal from an automatic detector that the fire
signature at a specific location had exceeded a user-configurable, low-level threshold value. That pre-
alarm signal did not create an actual alarm.
The pre-alarm state discussed here should not be confused with the pre-alarm state
discussed in Paragraph 4-10.5.
The pre-alarm state must be annunciated by distinctive public-mode notification.
Pre-Release State The pre-release state occurs when two automatic detectors (one detector from each of the two
crossed zones or any two detectors in a counting zone) issue an alarm report. The discharge
criterion for the waterless fire-suppression system is attained when the pre-release state occurs.
The pre-release state is also referred to as the countdown state because it typically triggers a
time-delay period that precedes the discharge of the waterless fire-suppression system.
The pre-release state must be annunciated by public-mode notification different from the pre-
alarm state public notification mode.
Release State The release state occurs when the waterless fire-suppression system discharges at the
conclusion of the time-delay period.
The release state can also be triggered without a time delay by a manual-release station. It is
also common practice to trigger a pre-action-sprinkler system concurrently with the discharge
of the waterless suppression system.
The release state must be annunciated by public-mode notification different from both the pre-
alarm-state and pre-release-state public notification modes.
Abort State The abort state occurs when an abort switch is manually activated to interrupt or prevent the
start of the countdown timer whose expiration will trigger the discharge of the waterless fire-
suppression system.
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