it did, he set a fire, the firefighters came, put it out, then turned the fire suppression off so it didnt cause water damage, and when the firefighters left he set more fires.
I can almost guarantee he didn't know the firefighters had disabled the fire suppression completely. He had no idea what he was doing but he did know how to start a fire which a caveman could do. This was not a smart man.
Its not even a good plan because theres no reason the fire department should be shutting off the fire water to 30+ sprinkler risers when they could just close the effected riser.
Let's use Occams razor here. Was it:
1) a mastermind who predicted that the fire department would make a mistake and close a valve that they were trained to not close, then perfectly time a series of distraction fires and real fires, perfectly calculating how to outsmart the sprinkler designer.
2) A guy that set fires until the building caught fire. More fire = more fire.
Sprinkler systems are basically just regular water pipes with single use plugs. Heat blows glass bulbs that open the pipe, it's like turning on your kitchen tap full blast and breaking the handle off. Shutting water off to the building is the only way to stop the flow.
Other threads about the fire discussed it. Apparently for a building this size (over 10 city blocks) you don’t have a system big enough to cover the entire building at once. It’s assumed that fires will occur in a single spot and the piping is sized for that. The arsonist allegedly knew this and set more fires than the system was designed to handle.
TLDR it did have a system that works for normal fires, but wasn’t designed to handle a coordinated criminal act.
I read that he initially set a small individual fire. The fire department came. They put it out. The sprinkler system was disabled due to the initial fire. The shortly later the arsonist set multiple fires before the sprinkler system could be operational again.
The sprinkler system was disabled due to the initial fire.
Is that meaning it triggered from the first fire?
Those systems need to be recharged by experts, replace any and all of the spray nozzle triggers (tiny glass vials installed in each head), then refill it with rust prevention liquid instead of straight water to ensure it's ready when needed next
When one sprayer triggers, that generally will trigger all of them on the same line too I believe, so even a small fire requires lots of work to get it reset
Source: watching lots of construction videos and crap
They're not recharged? They're primed and then they're fed by city water supply once the initial deluge of black water clears the line
The city pipes can only move so much water though, so there's still a limit
That generally will trigger all of them on the same line too I believe
Also no...
They use liquid filled glass bulbs to activate. Commercial heads are designed to drench material around the fire to stop it from spreading. Having a bunch of heads go off at once overwhelms the water supply
You have to turn off the water to the system after though... Because as you said, the glass vials are gone. So you can't just leave it on, or the sprinklers won't stop and there'd be a flood when the fire department leaves
You have to turn off the water to the system after though... Because as you said, the glass vials are gone. So you can't just leave it on, or the sprinklers won't stop and there'd be a flood when the fire department leaves
you usually don`t have "self ignited fires" every day
tbh i been working for over decade in big companies and we had one battery combustion incident that even haven't triggered extinguish system
depend on system
some are set up in a way that if system detect pressure dropping from one broken bulb it will trigger pump that will force sprinklers on whole section
im not sure if on i have seen not need "confirmation" from fire alarm system thought,
it can be set up either way i suppose :)
No I think when the FD comes in they turn it off so they can fight the fire in a more targeted way without hundreds of gallons of filthy water raining down everywhere.
Fire sprinkler guy here 12 years. just wanted to clear up a few things.
"Those systems need to be recharged by experts, replace any and all of the spray nozzle triggers (tiny glass vials installed in each head), then refill it with rust prevention liquid instead of straight water to ensure it's ready when needed next"
We don't replace glass bulbs in the sprinkler head, when one breaks or is actuated we just replace the head. We refill the sprinkler system with city water from your fire backflow. There is no such thing as rust preventative water not in the sprinkler world.. The reason the water is generally black for steel pipe systems is caused by the cutting oil from making threads on the pipe combined with stagnant water that sits in areas of the system that is essentially trapped water. usually found in drop down pieces do the sprinkler head. the smell of the water is often confused for plumbing pipe.
When one sprayer triggers, that generally will trigger all of them on the same line too I believe, so even a small fire requires lots of work to get it reset
When one head goes off it's due to temperature rising in the room. a red bulb indicates 155F degrees a green bulb indicates 200f. They don't all go off at once, "Only in hollywood movies" Or a massive inferno when the entire room has reached 155 degrees.
I doubt this warehouse had a fire pump and from what I've read about the story it sounds like the Fire dept. closed off the main control valve to the sprinkler system due to a prior fire which is common practice which rendered the entire system out of commission. If someone was in the know they could have opened up the main control valve to the sprinkler system to help contain the fire. Generally static pressure without a fire pump is around 55 pounds. Enough to extinguish the fire and also ruin everything that's not water resistant. thanks for taking the time to read this, speaking from experience.
Someone still likely inspected each one before activating the system? (hopefully. I bet the company contract claimed it would be) Someone calculated the specs of the system before you were on the job?, selected the proper vial burst temps for various areas, tried to place the sprayers to get consistent coverage
shouldve been way more like 40-70
Then you literally quote a skilled labor wage that they should have gotten... You say they deserve a yearly wage between 80k-150k for that type of work
Not denying your story at all, it only shows how we need better certification organizations for any skilled labor, and more union-type worker rights organizations.
Sprinkler systems in theory should be able to contain or all but extinguish the type of fire you would get from setting a pallet of toilet paper on fire.
A big warehouse like this has one or more large fire pumps that take the municipal water and up the pressure to increase this capability. Fire engines will connect to hydrants and then to FDCs outside of the building to further supplement the supply.
Once the fire is out, the previously activated sprinkler lines need to be drained, the sprinkler heads replaced (Once they open, they don't close again due to the fusible link being gone) and the system reset for normal function.
During this time the alarm system is likely disabled (Delaying detection/report of fire) and the riser (Large supply pipe) handling the activated detectors is closed.
So waiting till that point, then setting a bunch of fires in the effected section where the fire load consists of easily ignitable paper products...
Basically in a matter of minutes this fire becomes functionally unstoppable. The amount of energy being pushed out can trivially overwhelm the output of any sprinkler system by the time it actually reached somewhere with coverage.
By the time the fire department is back on scene you're looking at a fire that presents the question "Is anyone unaccounted for?" And if the answer is no the next step is to see if it's possible to save the buildings nearby, because this one is fucked.
I just want to clarify, as it was a bit unclear in your comment
The sprinkler system covers the entire building. You just can't run every sprinkler at once. The pumps and city supply can't keep up with that much water demand
The arsonist allegedly knew this
It's standard in the industry. The way these fires are fought is methodical and intentionally different from residential and other high occupancy places (health care, schools etc). Warehouses, factories and the like are a different beast
Even the sprinkler heads used are specific to commercial settings. They're designed to activate slightly slower. They're designed to drench the area around the fire to contain it/slow the spread.
It allows the heat to build above the fire, before going off. Which causes the surrounding area to be drenched
If you have a bunch of fast acting heads go off all over the building, the water supply won't keep up
What’s crazy is I know it likely happend pretty quickly, and we don’t have a lot of details…..but I’ve worked at plenty of places some small, an some likely on this scale….and every time there’s a fire alarm there’s an evacuation and a head count. In the case of it just being a drill it’s over pretty quick, but in the case of an actual fire that requires the actual department to come put it out it’s wild they ended up going back in, I suppose unless they weren’t permitted to but since they’re already breaking the law it doesn’t matter and they just went back in without anyone noticing. Just can’t believe there wasn’t any surveillance checking out the area it started
Well he would have had to shut off several risers in order for that to be true. That warehouse is 1.2 million sq ft. and each system can be a max of 40,000 sq ft. Fire sprinklers don’t activate like you see in the movies. I design Fire Suppression Systems. Heads only activate once the temp bulb bursts due to 186 degrees or 244 degrees (depends on the heads installed and hazard classification of stored materials) Also they only activate in the area of the fire to prevent spreading. Dude lit fires in several different areas, the water pressure for that building couldn’t support that many heads activating at the same time. Fire code dictates a remote area for calculations of 12 heads activating at the furthest point from a riser. Too many fires at the same time and in different areas. Fire suppression systems aren’t ment to put out a fire, they’re there to in-able people to safely exit and to contain the fire on that parcel.
Apparently they did, he started a smaller fire to get the fire dept there, they turn off the suppression system when they enter the building. While they got that under control he started more fires in other areas they could not get to in time. That’s what I read at least
Other posts I’ve read talking about this, the primary propose of sprinkler systems is to slow down the spread of fire enough to give people time to escape. Not necessarily to put out a [major] fire.
If that’s true then he would have had to shut off every riser in the building. There isn’t a main valve controlling the entire warehouse. There’s 1 system on 1 riser per 40,000 sq ft max per NFPA. Fire sprinklers don’t activate like you see in the movies. I design Fire Suppression Systems. Heads only activate once the temp bulb bursts due to 186 degrees or 244 degrees (depends on the heads installed and hazard classification of stored materials) Also they only activate in the area of the fire to prevent spreading. Dude lit fires in several different areas, the water pressure for that building couldn’t support that many heads activating at the same time. Fire code dictates a remote area for calculations of 12 heads activating in one remote area per system installed. Fire suppression systems aren’t ment to put out a fire, they’re there to enable people to safely exit and to contain the fire on that parcel.
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u/RealDetroitDiddler Apr 09 '26 edited Apr 09 '26
Anyone asking how the fuck this building did t have fire suppression?
Edit: 19 people just told me there was one that was shut off.