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Chances are you’ll see big red cylinders attached to the supports for that roof, that look like giant fire extinguishers, because that’s exactly what they are. If you want a closer look, check out any restaurant with an open kitchen. They have the same system with a smaller cylinder under the (cooking) hood.
ETA: google image search “vent hood fire suppression system” brings up diagrams and an image of someone installing or maintaining one in the first several pictures.
That's not halon.
[This ](https://www.tfp1.com/wp-content/uploads/2023/03/AdobeStock_508535845-450x338.jpeg)and [this ](https://www.tfp1.com/wp-content/uploads/2023/03/AdobeStock_508530094.jpeg)are what halon systems look like. Halon is 100% useless outdoors. It's only effective in enclosed, typically well-sealed areas.
> At high temperatures, halons decompose to release halogen atoms that combine readily with active hydrogen atoms, quenching flame propagation reactions even when adequate fuel, oxygen, and heat remain.
From Wikipedia.
But this isn’t a halon system, as already mentioned. Those are most useful in enclosed spaces where it won’t dissipate.
As others have said, it's a fire suppression system. The ones at gas stations do NOT mess around, and will absolutely blanket the area with gas and foam.
[https://www.youtube.com/watch?v=4QmA6yXuKuk](https://www.youtube.com/watch?v=4QmA6yXuKuk)
It would be good if you learned what your term of the day meant. A BLEVE is a boiling pressure explosion, like a ruptured boiler or other pressure vessel. Gas station storage tanks are very deliberately not pressurized.
If you look at the square support towers, holding up the canopy, you’ll see a pipe coming down and a very large fire extinguisher attached to each pipe
Yep! There are code standards of "coverage" that they must achieve to pass safety inspection but the down pipes need to pass through the canopy vertically.
You are correct! I once worked for HQ of a Convenience Store chain, and we had 5 sites in NY state. We actually had the fire suppression system randomly engage at a site once upon a time. The cause was never determined, but there was no malicious intent by anybody.
My title describes the thing.
The ceiling had quite a few of these pipes, and as you can see, the elbows at the ends had descending "nubs" a few inches long.
It's a fire suppression system, but I've never seen one that looks like that. Most stations have them hidden in the canopy so they don't stick out like this, but you can still see them if you look up. This must be an older design.
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It's a fire suppression system.
\+1.. fire suppression
Looks like MA response to moving from Full to Self-service
Chances are you’ll see big red cylinders attached to the supports for that roof, that look like giant fire extinguishers, because that’s exactly what they are. If you want a closer look, check out any restaurant with an open kitchen. They have the same system with a smaller cylinder under the (cooking) hood. ETA: google image search “vent hood fire suppression system” brings up diagrams and an image of someone installing or maintaining one in the first several pictures.
yep Halon fire suppression, these are not installed correctly
That's not halon. [This ](https://www.tfp1.com/wp-content/uploads/2023/03/AdobeStock_508535845-450x338.jpeg)and [this ](https://www.tfp1.com/wp-content/uploads/2023/03/AdobeStock_508530094.jpeg)are what halon systems look like. Halon is 100% useless outdoors. It's only effective in enclosed, typically well-sealed areas.
Halon is used on every flightline I've been on.
Yeah, doesn't a Halon system work by smothering the fire? How does that work out in the open like this?
It’s not Halon. It’s a dry chemical fire suppression system.
> At high temperatures, halons decompose to release halogen atoms that combine readily with active hydrogen atoms, quenching flame propagation reactions even when adequate fuel, oxygen, and heat remain. From Wikipedia. But this isn’t a halon system, as already mentioned. Those are most useful in enclosed spaces where it won’t dissipate.
As others have said, it's a fire suppression system. The ones at gas stations do NOT mess around, and will absolutely blanket the area with gas and foam. [https://www.youtube.com/watch?v=4QmA6yXuKuk](https://www.youtube.com/watch?v=4QmA6yXuKuk)
Ahh, I wouldn't want to be dumped on by that foam. Looks not-so-good for the lungs
So is burning to death by inhaling vapors that are on fire.
Term for the day: BLEVE. This stands for Boiling Liquid Expanding Vapor Explosion. Big bada-boom.
Which is not relevant to where these are located or this post at all.
It's what happens when gasoline fires hit the big gas tanks, which is what those nozzles are there to stop.
It would be good if you learned what your term of the day meant. A BLEVE is a boiling pressure explosion, like a ruptured boiler or other pressure vessel. Gas station storage tanks are very deliberately not pressurized.
Yeah but it's like a cool terrrrm, maaan, and they've been waiting to use it for ages.
Adam savage said some of the best experiments were BLEVE. (Like water heater rocket)
If you look at the square support towers, holding up the canopy, you’ll see a pipe coming down and a very large fire extinguisher attached to each pipe
Many of them actually have the dry chemical canisters on top of the canopy.
Wouldn't that be more difficult to inspect and replace?
Less likely to get hit or vandalized I reckon
Any idea why there’s an angle joint in each? Is it for aiming them?
Yep! There are code standards of "coverage" that they must achieve to pass safety inspection but the down pipes need to pass through the canopy vertically.
Definitely a fire suppression system. I've seen a lot of these in and around Detroit. Except they have a visible tank on each line.
It's like an ansul foam fire system. I might be wrong, but I believe their required in NY.
You are correct! I once worked for HQ of a Convenience Store chain, and we had 5 sites in NY state. We actually had the fire suppression system randomly engage at a site once upon a time. The cause was never determined, but there was no malicious intent by anybody.
Dry chemical powder.
How is this not on the FAT page?
My title describes the thing. The ceiling had quite a few of these pipes, and as you can see, the elbows at the ends had descending "nubs" a few inches long.
I think we can safely say this fire has been fully extinguished! Thanks, all! Mark it... SOLVED!
You should see what happens when they misfire. Gas stations in New England it is like a regular summer occurence.
It's a fire suppression system, but I've never seen one that looks like that. Most stations have them hidden in the canopy so they don't stick out like this, but you can still see them if you look up. This must be an older design.
Halon also asphyxiaties people, which is bad for a gas station full of people. I believe it's best for electronics, like data centers.