Smoke machines and fire alarms

jack.homer

Member
The drama dep has just got a smoke machine and the site team won't turn the fire alarm off unless there is some type of document saying what should happend and stuff can someone help


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It is usually considerably more than a 'document'. You will most likely have to contact your local Fire Dept. and have someone on-site during the performance (and they don't do it for free). Contacting them in any event is a good idea as they will tell you exactly what needs to happen.
 
My understanding is that is is completely up to your local authority (wouldn't it be nice to be standardized more?). You will have to jump through the hoops your fire marshall sets. This will include various documents for liability etc, and most likely setting up a "fire watch" (someone(s) to watch the venue for signs of fire).
Some buildings have ways to disable a PART of the fire alarm system. Some buildings don't even HAVE smoke detectors (they have heat detectors instead).

I'd contact the Fire Department and ask for a specific list of what they want you to do.
 
You mention department, are you at a university? Are you a high school? If higher ed, find your head safety officer and ask them what to do. Many universities have someone who can help you contact the AHJ and help you communicate with them as well as advocate for you. This will, however, require you to be able to speak with some knowledge about the machine in question. You should also bring a copy of the MSDS with you. Also as people have mentioned turning off fire detection systems most of the time come with the price of hiring someone to monitor the system or the space.
 
Yes, turning off or disabling the smoke alarms is a serious process. In general, you will need to have a "smoke watch," if you turn off the alarms. That usually entails one or two firemen stationed in your facility with radios and fire extinguishers while the alarms are turned off. This requires money. You should also make sure all of your equipment and facilities are up to code, ie. storage, fire extinguishers, electrical, and drapes to mention a few items or you may get your show shut down.
To do a test may require just contacting the alarm company or physical plant people to monitor the alarm while you test the smoke machine. This will at least let you know how the smoke will affect your alarms. I use a fast dissipating smoke fluid and test it each show using the maximum smoke possible. I have done the test and used smoke for about 13 years in my buildings without alarms. I notify physical plant and campus police with the dates and times of the shows and effects. This does require responsible and competent operators. Without this you will likely trip an alarm. Most often I have seen alarms tripped in the return air systems of the air conditioning systems.
Having a fire plan should be a normal part of any facility's operating procedure. It should include a fire drill for cast and crew for each show. Especially include the front of house personnel.
 
I can't add to the excellent advice already given about how to go about isolating smoke detectors - I've always been lucky enough to work in buildings where there is a timer switch which isolates necessary detectors for a specific length of time. What I will say, though, is don't even THINK about trying anything stupid like covering the detectors yourself - I've seen people do it (and then ripped the covers off) and it is possibly one of the most stupid things you can do. There will be a time when one cover is forgotten and then of course the alarms don't trigger and there is a world of trouble. You haven't mentioned it, so I am assuming you already know this - but I felt like it needed to be said anyway!
 
I was running effects and lights for a production of Phantom of the Opera. there is a scene in the play where the fire alarm goes off in the theater. I got a little crazy with the low lying fog machine and set the real alarms off, one line from when the alarm in the play goes off. everyone in the audience thought it was a brilliant way to pull them into the play when they had to evacuate the theater for real. The school however was not very happy with the bill they got from the real fire department. I ran through the show the day before and didn't set off any alarms with the stage FULL of fog but when the audience filled up the theater their body heat made the fog rise much quicker. my point is you can get away with a little fog depending on how far away the first detector is from the source and if you have smoke detectors or particle detectors.
 
This problem arises so much, and has been on my long list for a code change for quite a while, but what would that change be? Right now, in most new build, detectors are generally not required in sprinklered buildings - or more correctly the sprinkler is considered a detector and the alarm notifies occupants by way of flow detection. Where there is a requirement or need for more detection, heat detectors (and most heat detectors today are combination fixed temperature and rate of rise) can be used. This might be for a smoke vent, fire safety curtain, or other. Return air systems of a certain size - 3000 or 5000 cfm I can't recall - however, are required to have smoke detectors. Existing systems do indeed have smoke detectors in the air, but code changes don't usually affect existing work, though would affect a system replacement or upgrade.

So, short of getting smoke detectors out of return air systems, and not overlooking turning off the hvac for a period of time as a perfectly acceptable preventative measure, it would seem a codified approach that involves turning off the occupant notification - the alarm - and having a fire watch that does see if a detector that normally initiates occupant notification is the logical solution. It would seem the trick is coming up with a method for having someone at the venue approved and authorized to do all this, rather than having to call an alarm company to silence the selected detectors and someone from the fire service being required for the fire watch. I would imagine the "approval" process to be considered acceptable to be the fire watch would be somewhat akin to rigging certification or pyro licensing, but that criteria including training and testing is not simple.

I can't help if your answer is just turn it off but open to other ideas or approaches. It's become too common of a problem not to try to address through the codes and standards that prevent or restrict a legitimate and safe effect. After all, the pyro industry were successful in changing codes and allowing indoor pyro - over my strong objections - and still can after killing a 100 people - so atmospheric effects shouldn't be that hard.
 
In the church setting (incense and all) all of our detectors are heat detectors. We had smoke for years and they actually didn't trip, but, after a few years they went flakey. At 40 feet up, replacing a single detector is a big hassle. Checked with the fire marshal and HE recommended changing over to heat detectors. The only smoke detectors left are the duct detectors. We simply shut off the HVAC if incense is being used. The primary reason there are detectors in ducts is to provide warning if smoke is being transported through the HVAC. In the case of our system, smoke detection will sound the alarm and shut down the HVAC.
As for possible code changes, I think changes should be more on the fire-code end of things, with heavier reliance on heat vs smoke detectors. The number 1 cause of false alarms (according to our FM) are false alarms from smoke detectors, and a fire company can not fight a real fire if they are answering a false alarm.
 
The primary reason there are detectors in ducts is to provide warning if smoke is being transported through the HVAC. In the case of our system, smoke detection will sound the alarm and shut down the HVAC.

The detectors in return air ducts as you describe is what is required by codes, and it's to prevent the spread of smoke from one compartment to another, so for instances a fire in the auditorium doesn't result in smoke in the lobby courtesy of the hvac system. In the case of spreading smoke by hvac, heat detectors would not work or work as well.
 
Here at OU we have a really good rapport with the campus "Risk Management" (fire marshal) office. We invite them in for a test, and if needed we have them bypass the audible signal; but it still registers with the office (who then would send out an officer to inspect if there is an active trip during the by-pass). Most of our sensors are heat, not particle though.
 
Here at OU we have a really good rapport with the campus "Risk Management" (fire marshal) office. We invite them in for a test, and if needed we have them bypass the audible signal; but it still registers with the office (who then would send out an officer to inspect if there is an active trip during the by-pass). Most of our sensors are heat, not particle though.
That is commonly called a "two stage alarm", many campuses or large interconnected buildings have systems that prevent audible alarms for a set amount of time. Someone is sent to check, who can either fully engage the alarm or cancel it before the fire department is called. Very useful in situations where false alarms are unwanted and there is a staff that can do it. Generally after a short time without input they still will engage the alarm.
Normally pull stations are left so they will immediately sound the alarm.

I agree that there needs to be a change in code. YES you want to catch fires as soon as you can to prevent loss of life and property damage. But you also want to eliminate false alarms from known factors such as atmospherics in performance venues.

At the college I went to there are two theatres, the main stage we could fog and haze. The studio on the other side of campus would set off the in-duct laser detectors with a little bit of fog or haze. The prevents the use of atmospheric effects in the black-box studio, which is generally where lighting design classes are taught. Not cool.

I think HEAT DETECTORS are the way to go, with particle or smoke detectors put on a separate "zone" which can be made two-stage with a switch flip or some such. You want particle detectors sometimes, they are much more likely to catch a fire early on. But a way to make them and only them temporally disabled should be CODE in performance venues.

As mentioned earlier perhaps a timer that allows it to be disabled for a set amount of time. Whatever. No sense having false alarms, or having to have a "fire watch' or "smoke watch" of expensive fire-fighters JUST to have a simple atmospheric effect that MAY set off the alarm.

This is in part an issue of people coming up with rules who have no concept of the things the rules surround. They should consult with theatre people for specific code rules to conver theatre spaces. As someone whos worked as an electrician who installs fire alarm systems, and delt directly with installers in a venue I can say that they really have NO CONCEPT of what happens on and back stage.
 
This is in part an issue of people coming up with rules who have no concept of the things the rules surround. They should consult with theatre people for specific code rules to conver theatre spaces. As someone whos worked as an electrician who installs fire alarm systems, and delt directly with installers in a venue I can say that they really have NO CONCEPT of what happens on and back stage.

The NFPA committees generally welcome members in the user category. And anyone can submit proposed changes. But you have to take it to them, because they don't know there is a problem unless you tell them. Unfortunately, the last comment deadline for the 2016 edition of NFPA 72: NATIONAL FIRE ALARM AND SIGNALING CODE has passed, and first opportunity to comment for the 2019 edition is probably around early July of 2016. But good time to apply if you feel you would like to work on the committee.
 
Don't know if it's too late. But my theatre is in a school district all we do is call the local Fire Dept and have them put our system in "Test" the alarm will still go off but they won't respond

A great example of how local Fire Marshal's have a wide variety of options at their disposal. So the correct answer for anything like this is call your Fire Department and ask.
 
A great example of how local Fire Marshal's have a wide variety of options at their disposal. So the correct answer for anything like this is call your Fire Department and ask.

Exactly. I do fireworks for a living. Believe me - every town (and AHJ) is different. Some want to hover over you while you work, and others just want to know what time the show is so they can bring their girlfriend/wife/child/etc.

You just gotta call and talk to them.
 
If I may, I will jump in this conversation with a few random thoughts.

Smoke detectors really are looking for combustion - the actual threat. When a fire happens, there are four likely conditions that may occur.

1 - Flame: the Flame is the visible, gaseous part of a fire - the exothermic reaction (release of heat)

(accidentally hit enter as I was writing - will post edited version shortly)
 
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