I'm going to have a party and I had experiences previously with a smoke machine triggering smoke alarms, so I want to disable them temporarily during the party. How do you do that?

This is what the smoke detectors look like:

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    You should under no circumstance disable the fire alarms. Especially with a house full of potentially inebriated party goers. – Tester101 Aug 13 '14 at 19:44
  • @Tester101 sigh, I know you probably live in a country that's full of smoke alarms, but around here, most houses don't have them. It's nice that this house has it, but having a constant alarm is annoying (and wouldn't be effective anyway). – pupeno Aug 13 '14 at 19:52
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    A false alarm is not dangerous. Ignoring an alarm because you think it's a false alarm, is dangerous. – Tester101 Aug 13 '14 at 20:12
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    Disabling smoke alarms is clearly not a home improvement. – ben rudgers Aug 14 '14 at 4:32
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    @TylerDurden I don't know where you are getting those numbers. Looking at CDC's website on fire deaths and costs and the cost of a fire alarm install (amortized over 10 years) I get rough numbers around $50k-$100k per life saved. (Not $50M). Considering the insurance payout for negligent death these days is around about $10M, I'd say fire alarms are a bargain. And I'm neglecting property damage and heath costs of survivors of fires. The fact that insurance companies, employers and local govs insist on them tell me they've run the numbers and got similar results. – Paul Aug 14 '14 at 4:49

Your detector is a photo sensing type, in other words it has a light source and a light sensitive element and when the light gets blocked by the vapor from the fog machine, it trips the alarm. Other types (ion sensing for combustion gases; heat detecting) would not be tripped by a fog machine.

As suggested by @Tyler Durden, blocking the ports should work.

If this is indeed an institutional or educational or high-rise residential occupancy then I am afraid Mr. Tyler Durden is gravely mistaken about laws regarding the disabling (intentionally or by negligence) of life safety equipment, it is a felony.

I used to fight fire and save lives for a living, now I work to prevent fires (and fix up old houses too, LOL). The statement that "fire alarms are...worse then useless" would be ridiculous if it was not so irresponsible to say in a public forum. Next time you are performing CPR on an 8 year old kid who was dragged out of a mobile home with disabled smoke detectors I will listen to your asinine opinion.

  • I think if you start issuing legal opinions designed to frighten people, you cite the actual law involved, rather than just BS. In my state it is no way a "felony" to disable a smoke detector and in many situations it is necessary to do so. For example, during renovation repainting etc, all smoke detectors must be disabled because of the dust created. There are many other situations were deactivating a smoke detector is necessary. – Tyler Durden Jan 10 at 4:29
  • @Tyler Durden I don't give legal opinions. You should look up the laws in your state. mass.gov/service-details/massachusetts-fire-code. No BS. – Jimmy Fix-it Jan 10 at 7:07
  • You wrote "it is a felony". CITE IT, I want to see that so-called felony. – Tyler Durden Jan 10 at 11:01
  • Massachusetts Fire Code-NFPA1-10.7.1 states "Persons shall not render ...any fire-warning system or device inoperative or inaccessible." The only exceptions are for maintenance, testing, drills, alterations, or renovations. The penalty is "a fine of not more than five hundred dollars or by imprisonment for not more than two years."- Commonwealth of Massachusetts General Laws Part IV Title I Chapter 266 Section 11. A crime is generally considered a "felony" if it punishable by imprisonment for more than 1 year. I could give 2 s#its what you do or think at home; a dorm is different... – Jimmy Fix-it Jan 10 at 15:54
  • LOL, the fire code you cited is not a criminal statute, it is just fire code. The law you cited has nothing to do with the fire code. The law covers intentionally diabling fire SIGNALLING equipment 24 hours prior to fire, and is intended to be a penalty for arsonists who cut fire alarm wires. – Tyler Durden Jan 10 at 16:54

Too many false alarms can be an annoyance. If your alarm detects only particulate, consider upgrading your alarm system to one that detects ozone and heat produced by a legitimate fire. I'm pretty sure most smoke machines only produce a vapor condensate (particulate) and should not trip the more sophisticated alarm system.

If you do not own the equipment, then under no circumstances should you disable them even temporarily. The owner is not only likely complying with rules regarding rentals or high density living arrangements, but they are also protecting their own property. Evidence that safety equipment has been tampered with is cause for eviction. I would certainly evict my renters if I caught them bypassing a breaker, or plugging drain vents or overflows. Same goes double for something as important as fire safety. Let the owner/manager know that you are getting too many false alarms and let them know what causes them.

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    @TylerDurden I think he wants to prevent smoke alarms from ringing during a party. I provide that solution. – Paul Aug 13 '14 at 21:42
  • Exactly @TylerDurden, it's just for my birthday party. – pupeno Aug 13 '14 at 22:18
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    The importance of life safety systems as smoke detectors is directly proportional to the number of people in a building. It is inversely proportional to the self-preservation capability of those people and also to the likelihood that someone will exercise poor judgement. "What could possibly go wrong?" is asked in two ways. One increases the possibility of appearing on the local news, the other decreases it. – ben rudgers Aug 14 '14 at 4:28

You live in the UK, so UK law applies.

Own home

If it's your own home you can disable the fire detectors by taping over them. A better way would be to disable the detectors at the fire alarm control panel.


If the home is rented, you disable the detectors by calling your landlord and requesting that the detectors be temporarily disabled for your party. The landlord is obligated under law to provide fire detectors. Your tenants agreement will very likely state that you agree not to interfere with safety related provisions such as fire alarms.

Landlord responsibilities include providing a fire alarm. Not all fire alarms require smoke detectors but if there is a fire, things may go very badly for you, financially, if you have disabled the landlord's equipment without permission. The landlord or his insurance company are likely to seek to recover all costs from you.

I am not a lawyer but you probably don't have the time (or inclination) to seek proper legal advice about disabling landlord's fire detectors.


If they're not hardwired... you COULD disable them by removing the battery from each one. IF YOU DO THAT, leave it hanging OPEN so it's eyecatching.

If they ARE hardwired... you COULD disable them by turning off the breaker that serves them, AND if they have an internal battery, remove it and leave it hanging open.

If they're wired to a central alarm panel, then you COULD disable the entire panel.

If parties there are like parties here, though... they may sometimes include such things as drunken partygoers self-immolating with alcohol or doing any manner of other crazy... "stuff". You should be aware that any person who knowingly disables a fire alarm device is culpable for any deaths or injuries suffered by anyone as a result of that action.


I don't recommend disabling smoke detectors. But if you must you may be able to get covers for from building maintenance or the manufacturer of the detector. Then get guidelines from your local fire department in writing. Guidelines may include having a responsible adult hired as a fire watch whom will not drink or sleep and make it his responsibility to remove them or otherwise re enable the system as soon as any possibility of false alarms has passed. Or they may just say no just lose the mist machine and open a couple of windows.

  • No fire department will give you guidelines for babysitting a disabled smoke detector during a party. – Reinstate Monica -- notmaynard Jun 3 '15 at 21:22

This is an institutional fire alarm and cannot easily be disabled.

Your best practice is not to disable it, but to prevent cigarette smoke from reaching its detector. This can be done with paper and masking tape. Cut out pieces of paper that fit closely to the windows of the housing and tape them on in such a way that there are no gaps whatsoever.

After the party you can peel the paper off.

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    I wouldn't trust anyone to remember to re-enable safety equipment after a party and before drunk smokers start falling asleep. – Paul Aug 13 '14 at 21:27
  • @Paul I am here to answer questions, not give people lectures about their life. The smoke detector he has is a dorm room detector. If it goes off during a party, it will create a huge hassle, not only spoiling his party but inconveniencing the whole building. He needs a practical suggestion that will allow him to have his party, and he has every right to have a party without a false alarm going off. – Tyler Durden Aug 13 '14 at 21:43

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