# Smoke Detectors



## Cadmium6855 (Dec 19, 2010)

At my school we just bought a $300 hazer, everytime we use it the smoke alarms go off, and it triggers the entire school, because of this we can no longer use the hazer. Has anyone come up with a solution to this problem, I would really like to use the hazer for every show, but due to the restrictions, we can not. I heard of plastic covers that go on to the detectors and melt when there is actual heat, I don't know if these are real or not, but it would be nice if they were. Any help is appreciated!


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## BrockTucker (Dec 19, 2010)

Those plastic red covers do exist. I've never heard of them turning a smoke detector into a heat detector though. I've only seen them used when construction was putting a lot of dust into the air, to keep the dust from causing a false alarm.

I'm going to guess you're a student, so before anyone else says it, your school will have a company that maintains and monitors your fire alarm system. Working with them you (and your adviser/instructor) can likely come up with a solution, weather it's replacing the smoke detectors with heat detectors, creating a way to bypass the smoke detectors when haze is being used along with a plan to make that safe/legal or something else I've not thought of. Bottom line, do not do anything to modify a fire alarm system without all of the appropriate people being involved.


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## kiwitechgirl (Dec 19, 2010)

Cadmium6855 said:


> I heard of plastic covers that go on to the detectors and melt when there is actual heat, I don't know if these are real or not, but it would be nice if they were.



By the time the flames are high and hot enough to melt the covers, you'd all be dead from smoke inhalation....the ONLY answer to this is you need to talk to the local fire authority (not being in the States I'm not sure exactly who that would be) and find out if there is any SAFE and LEGAL way to isolate certain areas of the smoke detection system. DO NOT ATTEMPT TO ISOLATE ANYTHING YOURSELF because you will be breaking fire codes and placing life at risk. 

Our building is a heritage building (so subject to very strict fire regulations), but we are able to isolate the smoke detectors in the theatre on a half-hour timer - it's in the control room so the lighting operator can flick the timer back round when it runs out (this is perfectly legal and legitimate). It's only the detectors in the theatre proper that get isolated - we have a "tunnel" which runs under the auditorium from one side to the other and the detectors in there aren't on the isolation switch, the audience passageway which runs through the back of the theatre is the same, and even the dock area detectors stay live the whole time. This does mean that we have to be careful with how much smoke/haze we use, and where we position the machines, but with careful planning it works. Our fire plan and risk assessments take this isolation into account, which is why it is all legit.

I say again: DO NOT ATTEMPT *ANY* ISOLATION OF DETECTORS WITHOUT TALKING TO THE PROPER AUTHORITIES FIRST.


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## Les (Dec 19, 2010)

You want to use the hazer for *every* show?

In any event, I haven't heard of any such covers. They make something similar for renovation work, but they are NOT intended for your purpose and you can't use them. I don't feel like they would be safe anyhow, since you would probably want to be notified of a fire situation long before the heat is sufficient enough to reach the ceiling. The only option you have is to either push for the district to install a different type of detector, have the fire marshal disable the smoke detectors during show nights in your space and attend every show for a hefty fee, or do without the hazer. 

In my high school career we only used a hazer once, but didn't really miss much without it. Doesn't always have to be a rock show.

Edit: Wow, beat twice!


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## LXPlot (Dec 19, 2010)

The reason that your smoke alarm is going off is most likely that you have a visual alarm as opposed to an alarm that senses when it takes in smoke. If you had a sensor alarm, it would still go off if it sucked in too much fog, but that would have to be a lot of fog for it to do that. I reccommend talking to the fire department or whatever company does your schools fire alarm, and asking if it would be possible to switch the visual alarm for the other kind I mentioned. If they can, awesome, just make sure you have some sort of ventalation system or outtake fan so the fog doesn't pile up. 

If they can't, you're out of luck, but remember that a hazer really isn't that vital, you can still put one awesome shows without one. If it turns out that you don't have a visual alarm and it's still picking it up, I advise you to try and get a different hazer, something that runs a fog fluid that's supposed to not set off alarms or stuff like that.


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## DiscoBoxer (Dec 19, 2010)

Cad, I have worked extensively with fire alarm systems. The only plastic cover for detectors is exactly what has been mentioned earlier in this post, and those are ones that are designed and only allowed to be used for the installation/construction phase. Even if someone has told you they have used them, YOU CANNOT once your building is issued occupancy by the local authority. Doing so would be against NFPA code and you do not want to consider such ideas.

You likely have a photoelectric or Ionization type detector. Both would be triggered if a decent haze was in their spec'd cover zone. What you would want to do is contact whoever is responsible for the fire alarm at your facility, contact the contractor who does your regular maintenance of the system, and ask them about the possibility of swapping the detector(s) for a "Rate of Rise type Heat Detector". While NFPA may allow the use of the device in your configuration (hard to say without knowing more), your local codes may not allow this type of device without having a photoelectric/ionization type detector in the area.

Contacting the contractor will answer your question on the best possible solution, that will keep you in compliance and keep your people safe.


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## mstaylor (Dec 22, 2010)

Some systems will allow you to isolate the ducts so they show a fault but doesn't kick the system. This requires a person monitoring the system when in this mode, then an efficient method of checking the fault. DO NOT attempt this without contacting the alarm company and the fire marshal. Any time you deviate from the approved fire system you have to the new plan accepted.


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## Anonymous067 (Dec 23, 2010)

Who spent (wasted...?) the money on the hazer before they checked if they could use it?


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## DiscoBoxer (Dec 28, 2010)

Anonymous067 said:


> Who spent (wasted...?) the money on the hazer before they checked if they could use it?


 
Surprisingly, this happens a lot. There are a lot of folks who don't have formal training or who are just starting out and are forced to learn the hard way through experience. The good news is that Cad will now know things to consider on the next venture that he will be asked to use/buy a hazer. 

This is the awesome thing about Control Booth. It gives us all access despite our experience, to connect with those in the know. Knowledge is power and everyone on the forum can contribute by asking questions, answering them, and challenging them from experience. Even though I think I know quite a lot, this forum has taught me that there is much much more to learn......even on things I thought were basic.


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