Re: 3 Wire Smokes?

["FIRETEK" <firetech(change-the-ch-to-k)@telus.net>]

In Line.


"Robert L Bass" <no-sales-spam@bassburglaralarms> wrote in message
news:kMSdnQiDrs2voCHYnZ2dnUVZ_ualnZ2d@xxxxxxxxxxxxxx
> >>> There's no such thing as a fire prevention
> >>> company.
> >
> > If you compare and contrast futures of a
> > typical burglar alarm system versus a
> > typical fire alarm system, and the words
> > detection versus prevention, I think
> > prevention is more valid for fire alarm
> > systems.
>
> With all due respect, Roland, how many
> fires do you suppose the average fire alarm
> system prevents?

That depends on whether or not the system activates early enough to prevent
an actual flame from developing.  Fire "prevention" companies do a great
deal more than simply testing whether or not the devices that form part of a
fire alarm sytem funciton as intended.  You wouldn't know this because
you're in "denial" that there's any such thing as a "fire prevention
company".

>  I would say the percentage
> is less than that of burglaries which a burglar
> alarm prevents.

Does a burglar alarm actually "prevent" a burglary?  If you believe in the
"hype" that's frequently presented in radio advertisements, perhaps.  If
*you* say it often enough, maybe.  Most of us take steps beyond the
installation of a burglar alarm, though.  You just sell "parts" so you
wouldn't be aware of all this.

>  Think about it for a minute
> (Cracker will need several days).  It's safe to
> say that some thieves decide not to burglarise
> a particular place because there's an alarm.
> A certain percentage stop and retreat upon
> hearing the alarm.
>
> Fire neither knows nor cares if there's an
> alarm.  It consumes whatever it can,
> regardless of the existence or activation of
> a fire alarm.

Not necessarily.  If you can prevent a fire from developing into a full
fledged conflagration (through early detection), then you'll minimize the
damge to property and the risk to life.


>
> > Other than say a man trap on an access
> > control system there is little "prevention"
> > offered form a burglar alarm system,
> > mostly it is for detection.
>
>
> > A fire alarm system can not only detect fire,
> > it can offer "prevention" of sorts.  A fire
> > alarm system can be designed to close
> > doors (like in nursing homes and hospitals),
> > close dampers, turn off air handlers, recall
> > elevators, and even activate fire suppression
> > systems like Ansul or other chemical fire
> > retardant chemicals in a computer room, or
> > communications closet for example...
>
> This may be more a matter of semantics, but
> IMO those are all responses to a fire once
> detected -- not prevention of the fire in the
> first place.
>
> > Although that might not "prevent" the
> > actual fire from starting, it can help to
> > slow or even "prevent" the fire from
> > spreading...
>
> Certainly suppression systems can well,
> suppress a fire but in most cases the
> suppression system activates the fire alarm
> -- not the other way around.  Even an Ansul
> system is usually activated by heat rather
> than an alarm system.

Then you know nothing about the fixed supupression systems that employ
agents lilke Halon 1301, CO2 or interface with water based deluge systems.
Smoke detectors are most often used and a releasing panel made by such
manufacturers as Notifier, Potter, Siemens, and Edwards are usually at the
"head end".  In some computer rooms, it's often desireable to release the
Halon (or the newer so-called "clean agents") before the heat from a flaming
fire can damage equipment.  The rooms are sealed, air conditioning and power
circuits are shut down, and the agent is allowed to "soak" the room it's
protecting until fire fighting personnel arrive and are able to identify and
deal with the source of the trouble.


>
> Fire doors and dampers close or, in the case
> of exterior doors, release upon alarm first to
> prevent the spread of smoke and to speed
> egress of persons on the premises.  They can
> slow the progress of fire but in the absence of
> a sprinkler system they don't usually stop the
> eventual spread of the fire.

The point is that if you can detect the fire in the early stages, you have a
better chance of ensuring it doesn't "progress" to something that could
become unmanagble, or risk life and property.