(See Note A-3.2.4.18.)
(1)
Except as permitted by Sentence 3.2.4.19.(2) and except as required by Clause 3.2.4.4.(2)(d), audible signal devices forming part of a fire alarm system shall be installed in a building so that
(a)
alarm signals are clearly audible throughout the floor area, and
(b)
alert signals are clearly audible in continuously staffed locations, and where there are no continuously staffed locations, throughout the floor area. (See Note A-3.2.4.18.(1))
(2)
The sound pattern of an alarm signal shall conform to the temporal pattern defined in Clause 4.2 of ISO 8201, “Acoustics — Audible emergency evacuation signal.” (See Note A-3.2.4.18.(2))
(3)
The sound patterns of alert signals shall be significantly different from the temporal patterns of alarm signals. (See Note A-3.2.4.18.(3))
(4)
In all normally occupied spaces, the fire alarm signal sound pressure level
(a)
shall be not more than 110 dBA when measured at a distance of 3 m from the device, or
(b)
is permitted to be more than 100 dBA provided the sound pressure level measured 2 000 mm above floor level is not more than 100 dBA. (See Note A-3.2.4.18.(4))
(5)
The sound pressure level in a sleeping room from a fire alarm audible signal device shall be not less than 75 dBA in a building of residential occupancy when any intervening doors between the device and the sleeping room are closed. (See Note A-3.2.4.18.(5))
(6)
Audible signal devices in sleeping rooms in a building of residential or care occupancy shall emit a low frequency signal. (See Note A-3.2.4.18.(6))
(7)
Except as required by Sentence (5), the sound pressure level from a fire alarm system’s audible signal device within a floor area shall be not less than 10 dBA above the ambient noise level and not less than 65 dBA, when any intervening doors between the device and the rest of the floor area are closed.
(8)
Except as permitted by Sentence (12), audible signal devices located within a dwelling unit shall include a means for them to be manually silenced for a period of not more than 10 min, after which time the devices shall restore themselves to normal operation. (See Note A-3.2.4.18.(8))
(9)
Audible signal devices within a dwelling unit or a suite of residential occupancy shall be connected to the fire alarm system
(a)
in a manner such that a single open circuit at one device will not impair the operation of other audible signal devices on that same circuit that serve the other dwelling units or suites of residential occupancy, or
(b)
on separate signal circuits that are not connected to the devices in any other dwelling unit, public corridor or suite of residential occupancy. (See Note A-3.2.4.18.(9) and (10))
(10)
In a building or part thereof classified as a residential occupancy,
(a)
separate circuits shall be provided for audible signal devices on each floor area, and
(b)
audible signal devices within dwelling units or suites of residential occupancy shall be wired on separate signal circuits from those not within suites of residential occupancy or dwelling units. (See Note A-3.2.4.18.(9) and (10))
(11)
Audible signal devices shall be installed in a service space referred to in Sentence 3.2.1.1.(8) and shall be connected to the fire alarm system.
(12)
Audible signal devices within dwelling units that are wired on separate signal circuits in accordance with Clause (10)(b) need not include a means for manual signal silencing as required by Sentence (8), provided the fire alarm system includes a provision for the automatic signal silence within dwelling units, where
(a)
the automatic signal silence cannot occur within the first 60 s of operation or within the zone of initiation,
(b)
a subsequent alarm elsewhere in the building will reactuate the silenced audible signal devices within dwelling units,
(c)
after a period of not more than 10 min, the silenced audible signal devices will be restored to continuous audible signal if the alarm is not acknowledged, and
(d)
the voice communication systems referred to in Article 3.2.4.22. and 3.2.4.23. has a provision to override the automatic signal silence to allow the transmission of voice messages through silenced audible signal device circuits that serve the dwelling units. (See Note A-3.2.4.18.(12))
(13)
If a 2-stage fire alarm system has been installed with an automatic signal silence as described in Sentence (12), the system shall be designed so that any silenced audible signal devices serving dwelling units are reactuated whenever an alarm signal is required to be transmitted as part of the second stage. (See Note A-3.2.4.18.(8))