Smoke Detectors for elevator recall in parking garages

[R Brown]

Anyone have an opinion on the use of smoke detectors in close proximity to
parking spaces above or below grade for use in elevator recall? Would a
particular type of smoke or heat detector be better? I realize it is up to the
AHJ, but was wondering how serious are the problems with false alarms and if
ionization or photoelectric detectors would be more prone to false alarms.

Thanks,

Ron Brown

[Mark LoCoco]

If these elevator lobbies are not enclosed areas and subject to car exhaust, you
may want to consider a photo detector with adjustable sensitivity (lower). The
AHJ may also consider a cross-zoned arrangement in these areas or perhaps allow a
long alarm verification on these detectors. Cross zoning would require both
detectors in the lobby to alarm. Alarm verification is a feature available on
some panels that will require the detection of smoke for a pre-determined time
before indicating at the panel. The detectors for the shaft should not be exposed
to car exhaust as the shaft should be fire rated and sealed. For the particular
detector to use, consider ambient temperature and humidity and select an
applicable device.

Heat detectors are not used for recall because their response is too slow. They
are generally used in sprinklered shafts to initiate a shunt trip and disconnect
electrical power before the sprinkler head opens.

Hope this helps,

Mark LoCoco
Qubic Technology

[mathieu...@bedison.com]

Mr. Brown,

I recommend that you use Rate Compensated or Fixed temp heat detectors in the
parking garage, above car's and such. Smoke detectors in the elevator lobby
and top of shaft. By using aux contacts on the fire alarm zone and mother
board will supply you with general recall and alt floor recall. You do not
want to use smoke detectors in the open parking area ( Due to the combustion
of car engines). Smoke detectors are used for life safety ( Office
buildings, dorm rooms, hospitals etc.) heat detectors are used for property
protection. Hope this helps

Mathieu

In article <7fis09$jej$1...@list.umaryland.edu>,

rbr...@fm.umaryland.edu (R Brown) wrote:
>
> Anyone have an opinion on the use of smoke detectors in close proximity to
> parking spaces above or below grade for use in elevator recall? Would a
> particular type of smoke or heat detector be better? I realize it is up to the
> AHJ, but was wondering how serious are the problems with false alarms and if
> ionization or photoelectric detectors would be more prone to false alarms.
>
> Thanks,
>
> Ron Brown
>

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