What is the loudest fire alarm you've heard?

I’m wondering which alarms people think are the loudest alarms. My loudest is the outdoor intercoms at my school. I know that intercoms aren’t technically fire alarms, but at my school the intercoms make a loud horn noise and the outdoor ones are very loud.

In the electronic alarm category, I think the TrueAlert is the loudest fire alarm ever. Not only is it loud; the waveform it produces creates beating with other TrueAlerts with slightly different tones, creating a disturbance much like the EAS attention signal. As loud as it is, it is very effective.

The ones at my school aren’t that loud. They don’t even hurt my ears, even when they’re going off next to me. Could there be some NFPA / AHJ requirement making a volume limit on school fire alarms?

Yeah for some reason when they remodeled my HS they put true alert h/s in the nurses office which is like probably 12x12 and they also put it in a 15x15 room which is the special Ed room. What idiot didn’t read the work order for a strobe there? XD

Since this was a remodel, the plans and specifications most likely were done by an architect and engineer. The fire alarm, including every horn, horn/strobe, and strobe only are drawn on the plans by the electrical engineer or fire protection engineer. In most municipalities those plans are submitted to the fire department for review and approval.

These jobs are usually installed by an electrical contractor and checked out by the contractor and Simplex tech. It is not their job to make decisions as to what devices go where. It is their job to install what the engineer drew on the plans. If the engineer drew a horn/strobe in those small rooms, that is what is installed. Any deviation ends up on the punch list for correction to what the engineer specified. And you don’t get paid extra for correcting punch list items.

I know those devices can be painfully loud in a small hard walled room. A request can be made to the engineer or the AHJ to change to a strobe only or reduce the sound level. That is the procedure to make that change. There is an accessory for Truealarm devices to reduce the sound level.


Optional Sound Damper; package of 20; field installed adhesive backed

horn output attenuator; reduces output 5 to 6 dBA

NOTE: After Sound Damper installation, measure sound level to ensure

compliance with applicable code requirements

might consider the high possibility of hearing impaired people in the special ed room need the extra loudness.

(sorry for double post, wouldn’t let me add to the previous one)

Code says you need to be 15dB above ambient, can’t be over 105 or 110dB I think. TrueAlerts do a max of 90dB so no problem there.

The catch is if the TrueAlert is in a hallway with an ambient of 60dB, it still has to be 15dB above the ambient inside of a classroom with the door closed. It could have a significant drop through a closed door, so even if the classroom is 60dB ambient, the truealert in the hall might need to be at 90dB to overcome the closed door and still get 75dB in the classroom (15 above 60dB ambient is 75dB). This means sitting in a classroom it might sound kind of quiet, but when you walk into the hallway you get blasted.

Speakers tend to be quieter than horn strobes, and there is usually more of them.

Isn’t the strobe FOR the hearing impaired?

then the visually impaired. :smiley:

the newer codes to separate out hearing impaired versus handicapped rooms now. spec ed would still be considered handicapped requiring both i would assume.

I second the TrueAlerts, although that might be because they’re the alarm I’ve had the most exposure to. They were in my schools from 3rd - 8th grade, and alarms never seem as loud when you’re setting them off in a controlled environment compared to a fire drill at school. Seems like a popular answer to this question could also be SpectrAlert Advances, but that again makes me wonder if people perceive them as being so loud only because it’s what they’re exposed to the most.

Edwards fire horn! :lol:

Probably, if you mean the one that’s your avatar. We were caught up in the electronic horns, we completely forgot about mechanical horns.

For electronic horns, I’d have to agree with the Truealerts. Those things are deafening at times. For mechanical horns, I’d have to go with the Edwards 311 fire horn.

Hands down





For electronics, the SpectrAlert Advance.

I agree with TrueAlerts. Both my elementary and middle schools had them, and they were extremely loud.

Yeah, SpectrAlert Advances and TrueAlerts sure are pretty loud. I know this from testing my TrueAlert, and the Walmart I used to work at had SpectrAlert Advances. In the back maintenance/receiving area, they were really obnoxious and ear-piercing. But in the break room, we had one in it and it wasn’t that bad; I guess it was set on “low” volume.

I find electromechanical/vibrating horns to be worse. The loudest I’ve heard out of all of them would have to be the Simplex 4040s at my high school (my brother now works there), set on Continuous. Tying for second loudest would have to be the Simplex 4051 horns in kindergarten (they’re gone now) and the old explosion-proof Federal horns from the '50s at my middle school.

For electronics: Gentex Commander 2 and 3’s set to Mechanical.

For mechanical: Simplex 2901-9833 and Federal 450D

Sorry, the TrueAlert and Advance are louder; trust me.

Those could be the loudest he has heard though. Its in the topic name.

facepalm Derp! My bad!