Shop Heating and Fire Detection

[Larry Frank]

I have been reading with a great deal of interest several of the threads on heaters and the potential fire problems with them.

Does anyone use a smoke or heat alarm in their shop? I would rather have a smoke alarm but the fine dust will probably cause a lot of false alarms.

I am thinking of putting in a heat alarm. I have a Honeywell Vista security system and am thinking of adding a heat sensor. The sensor will alarm if the temperature rate of rise is 15°F or higher or the temperature exceeds 135°F.

What are others doing for fire protection?

[matt swiderski]

I have a smoke detector in my shop (used to be a 2 car garage, wife still calls it that). And it has never gone off. It might depend on the type of smoke dectector, either ionization or photoelectric. Not sure which type mine is though. According to Wikipedia, "Optical or "toast-proof" smoke detectors are generally quicker in detecting particulate (smoke) generated by smoldering (cool, smokey) fires. Ionization smoke detectors are generally quicker in detecting particulate (smoke) generated by flaming (hot) fires." So maybe an ionization type smoke detector might give you less false alarms. Hope this didn't confuse you any.
Matt

[matt swiderski]

It would be nice if I could remember the whole post after I hit the reply button. I would go with the temperature sensor. Less chance of a false alarm.
Matt

[Bill LaPointe]

Hve a smoke alarm in my shop. Only time it has gone off is if I am brazing or welding. Never had an alarm with any wood cutting machines, including before a good dust collector.

[Matt Meiser]

I have heat detectors wired into the security system. The alarm company said they won't monitor a shop with smoke detectors due to false alarms which result in an immediate call to the fire dept.

[Matthew Sherman]

Don't forget carbon monoxide detector as well if you have a gas heater.

[Bill ThompsonNM]

It seems to me that if the air temp is 135, you're way behind in dealing with a fire! Perhaps a better strategy would be ac smoke alarms powered off when the lights are on. Then temp alarms if you are using a monitoring service -- always on.

[Chris Jackson]

I run a dual head catalytic propane heater in a converted 2 car garage based shop (35'x20') and have a battery operated CO detector...never had any problems.

[Aaron Montgomery]

I have heat detectors wired into the security system. The alarm company said they won't monitor a shop with smoke detectors due to false alarms which result in an immediate call to the fire dept.
I've got the same setup. Heat detector in the shop, installed by the alarm company.

[Terry Rasmussen]

After returning home Friday, I walked in to shop to smell burning paint. The blower on the 7 year old garage heater had failed, but gas valve stayed on despite having an overtemp switch. I never got around to extending fire alarm to shop. However, I will now. I would suggest mounting alarm above heater as in my case the temp within a foot or so was high enough to trip it temp sensor.

[Mike Cutler]

It seems to me that if the air temp is 135, you're way behind in dealing with a fire! Perhaps a better strategy would be ac smoke alarms powered off when the lights are on. Then temp alarms if you are using a monitoring service -- always on.

Bill
I cannot state for residential applications, but for industrial applications heat detectors are a kind of "2 for 1" device.
There is a bimetallic strip that closes a contact on an absolute high temp condition,and a second bimetallic strip that is wound into a helix to act as a rate of change device. If air temp changes too much in too short a time the heat detector considers it a valid condition.

The optimum system is a combination of photo cells and ion chambers for Class A combustibles. I know that some folks alarm services seem to disagree, but that doesn't make a lot of sense to me.
The design of either detector type would mitigate inadverdent alarm conditions due simply to airborne particulates by virtue of physical design construction and operation.
If I were to install a system it would smokes for the general area and heats in any application where there would be more Class B, or C combustible loads.
Outside of photo cells and ion chambers there are I/R, infared devices that look for flame signature. They are very expensive and I wouldn't expect to find them used in a residential application.
Smoke detectors are your best bet for Class A combustibles. They're cheap and they work.


I've been installing,maintaining, and testing fire suppression/detection systems for 20+ years.

[Matt Meiser]

By the way something to keep in mind--if you've got a detached shop, an detector that isn't either monitored or doesn't somehow sound in your house is all but useless. Chances are if you are in the shop you'd notice a fire before the detector (probably before it was much of a fire) and if you aren't in the shop, who is going to hear it?

Obviously this doesn't apply to CO detectors.

Mike, I had multiple companies tell me they couldn't do smoke detectors in my shop. I know the ones in the house are photocell detectors. Has the technology changed much in the past 7 years? Maybe I should re-investigate what is available today. The heat detectors probably only serve as a courtesy call to the fire dept but at least they satisfy my insurance company for premium discount purposes and only cost about $30 to install.

[Phil Thien]

I've been installing,maintaining, and testing fire suppression/detection systems for 20+ years.

Any makes/models of general-use detectors to use in the home? I'd specifically like something that has unit-to-unit communication (so if the 1st floor detector is tripped it trips the other detectors in the house). I checked one on Amazon and they complained it chewed through batteries like there is no tomorrow.

Due to the construction of the house it would be difficult to permanently wire them, so I'd prefer battery operated. If you know of any, that is.

[Matt Meiser]

Phil, when my parents' redid their kitchen they had to put some in but I don't know what brand they are. According to the builder most municipalities around here are requiring retrofit of a communicating smoke detector system on any building permit and wireless is permitted. I got the impression they are commonly available.

Edit: so The Man must be tracking me. Today's Woot: First Alert ONELINK Wireless Smoke Alarm 2-Pack $39.99 + $5 shipping
http://www.woot.com/

[Lee Schierer]

Matt, I've had an ionization type smoke detector in my shop for 25+ years. It has never gone off due to sawdust, despite a few really dusty occassions. It does go off every time I use my branding iron to brand a completed piece or do any soldiering that when I don't remember to remove the detector before beginning work. You could also opt for a heat detector type like those used in kitchens.

[Phil Thien]

Edit: so The Man must be tracking me. Today's Woot: First Alert ONELINK Wireless Smoke Alarm 2-Pack $39.99 + $5 shipping
http://www.woot.com/

That woot was what kinda led me to the question. The Amazon review of that product said it was a battery eater.

[Matt Meiser]

Phil, I'll ask my dad about battery life and model when I'm at their house this weekend. They've been in for a year now so he should have a pretty good idea.

I'd hazard a guess though that any wireless system is going to use more battery power than a non-communicating smoke alarm because they have to power the radio. It doesn't have to be transmitting all the time, but it does have to listen. Buying more batteries would be the tradeoff of having to run wire in a retrofit.