this post was submitted on 24 Apr 2025
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Aside of these signs and the address numbers, the building is completely unmarked.

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[–] Agent641@lemmy.world 4 points 21 hours ago* (last edited 21 hours ago)

Likely it's a water treatment plant, probably a dosing plant for drinking water. Signs indicate which kind of chemical hazards are present, stored in relatively large and concentrated quantities.

No other signage because it's critical infrastructure, and if you need to know, you know.

Dosing buildings like this are common downstream from dams and reservoirs. Where I live, they are also mostly unmarked and heavily fenced off. Same as electrical substations, phone exchanges and other infra.

[–] mic_check_one_two@lemmy.dbzer0.com 76 points 1 day ago* (last edited 1 day ago) (1 children)

Those are hazardous chemical markers. You commonly see them on tanker trucks as well.

The numbers range from 0 to 4, with higher numbers indicating more risk. The red top corner is flammability. The right yellow corner is instability; How likely it is to react with other things around it. The left blue corner is risk to health; Even if a chemical isn’t unstable or flammable, it can still be hazardous. The bottom white is for special markings. In this case, one of those chemicals is marked with a W, meaning it reacts to water.

So if there’s a fire at the warehouse, this tells the responding crew “hey just so you know, there’s some nasty shit in here. One presents a severe health hazard, becomes potentially explosive when heated, and reacts with water… But at least it isn’t flammable. The other is flammable and can present a moderate health risk. Because of the one on the left, it would be a bad idea to use water to fight this fire.”

[–] barneypiccolo@lemm.ee 1 points 21 hours ago

100% correct answer.

[–] snugglesthefalse@sh.itjust.works 15 points 1 day ago (6 children)

Here's my favourite warning, can you guess what it is?

[–] markovs_gun@lemmy.world 8 points 1 day ago

Holy shit fours on blue AND yellow, AND it's an oxidizer? My guess is some kind of halogenation agent, likely fluorine based. The lack of flammability with those stats makes me think it's an inorganic compound, probably some wretched fluorine abomination.

[–] Laristal@lemmy.dbzer0.com 11 points 1 day ago (1 children)
[–] unbanshee@lemmy.dbzer0.com 1 points 1 day ago (2 children)

Seems like it would definitely not have a 0 in red?

But it was a great read and I'm glad you posted it.

[–] snugglesthefalse@sh.itjust.works 1 points 20 hours ago* (last edited 20 hours ago)

It makes most things it touches flammable but won't ignite by itself

[–] markovs_gun@lemmy.world 2 points 1 day ago

Oxidizers aren't typically flammable themselves and only react with fuels.

[–] SoleInvictus@lemmy.blahaj.zone 13 points 1 day ago* (last edited 1 day ago) (2 children)

Chlorine trifluoride! Nasty, NASTY shit. Guess which industry I worked in as safety!

Edit: I remembered this quote about ClF~3~ from John D. Clark's book "Ignition!" and wanted to share. For the non-scientists, hypergolic means it'll ignite on contact with another substance without an outside energy source, like a spark.

It is, of course, extremely toxic, but that’s the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.

[–] Agent641@lemmy.world 2 points 21 hours ago (1 children)
[–] snugglesthefalse@sh.itjust.works 1 points 21 hours ago

Yeah it basically is, also while it's not flammable itself, it makes almost everything it touches ignite. Even the very unburnable things

[–] SirQuack@feddit.nl 8 points 1 day ago (1 children)

Wikipedia screenshot of hazards of chlorine trifluoride, showing hazard symbols for explosive, corrosive, tozic and carcinogenic with the word "Danger" below it

I think "Danger" might be putting it lightly...

[–] SoleInvictus@lemmy.blahaj.zone 11 points 1 day ago (1 children)

Hah! You get two signal words with GHS: caution or danger. Caution is low stakes, where you might get skin irritation or maybe a mild burn. Danger is supposed to clue you in that it will fuck you up, but there's no indicator of magnitude of fuck you up. Will it just give you a bad burn or will it melt your skin off while intercalating with your DNA?

I always wanted a third "oh helllll no" category for the really awful substances. For things like tert-Butyl hydroperoxide (it's a straight 4-4-4) or Osmium tetroxide.

[–] markovs_gun@lemmy.world 1 points 1 day ago

Same dude. Like signal word "Fuck" for the spiciest of chemicals that really probably shouldn't exist in the first place that are desperately trying not to exist

[–] x00z@lemmy.world 9 points 1 day ago

404 not found

[–] SirQuack@feddit.nl 5 points 1 day ago* (last edited 1 day ago)

If I'm to understand mic_check_one_two@lemmy.dbzer0.com correctly, it's something that's:

Extremely hazardous,
non flamable, Extremely unstable, Reactive to water

And if ox means oxidising, reacts to exposure to oxigen.

I thought Lithium, but that catches fire and this is non-flammable.

I haven't a clue what this could be, but now I'm curious.

[–] jet@hackertalks.com 180 points 2 days ago* (last edited 2 days ago) (1 children)

Those diamonds indicate what chemical hazards are inside the building, for fire and rescue operations.

https://en.wikipedia.org/wiki/NFPA_704

[–] dohpaz42@lemmy.world 33 points 2 days ago
[–] Blaster_M@lemmy.world 124 points 2 days ago (3 children)

So in that building there's a nonflammable reactant that's super dangerous to life and reacts with water, and a flammable chemical that is quite toxic.

[–] Zombiepirate@lemmy.world 53 points 2 days ago (2 children)

So... Bring my HEV suit and crowbar?

[–] Yermaw@lemm.ee 39 points 2 days ago (1 children)

They're waiting for you, OP, in the test. Chamberrrr.

[–] xavier666@lemm.ee 7 points 2 days ago* (last edited 2 days ago)

OP doesn't need to hear this. OP's a highly trained professional.

[–] essell@lemmy.world 16 points 2 days ago

Depends, are you in the tank today?

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[–] AbouBenAdhem@lemmy.world 50 points 2 days ago (1 children)
[–] dohpaz42@lemmy.world 13 points 2 days ago
[–] queermunist@lemmy.ml 23 points 2 days ago (4 children)

As others have said, these are NFPA signs.

What I want to know is why there are two different ones. What the hell does that mean?

[–] mic_check_one_two@lemmy.dbzer0.com 4 points 1 day ago (1 children)

It means there are two separate chemicals inside of the building. Each chemical would have their individual labels on their containers, but these external signs are for first responders who haven’t entered the building yet.

Let’s say there’s a fire. The red diamond tells them how likely it is that the chemicals are the cause of the fire, and where they should direct their efforts. The blue corner tells them what kind of PPE they need to use if they enter. The yellow tells them what kind of potential explosive risks the chemicals have. And the white one is especially important, because the W means the chemical reacts with water; If there’s a fire at the facility, they can’t simply use fire hoses to fight it.

The reason for listing them separately is because each individual chemical has its own ratings. You can’t simply take the highest of each and combine them into a single sign. For instance, in this case one chemical isn’t flammable but is explosive when heated. The other chemical is flammable but not explosive. So if you see a chemical on fire, you know it’s the second chemical and isn’t explosive. But if you see something that isn’t burning in a room full of fire, you know it’s a potential powder keg waiting to explode.

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[–] Devadander@lemmy.world 34 points 2 days ago (1 children)

Two different chemicals to be aware of

[–] queermunist@lemmy.ml 4 points 2 days ago (4 children)

But it's just slapped on the side of the building with no indication of which chemicals the labels are for, I don't think that's how it's supposed to be done. It'd be like mixing two chemicals into a bottle and then putting two labels on it.

I think there should just be one label that combines the warning levels of both i.e. 3-2-2-W

[–] SoleInvictus@lemmy.blahaj.zone 2 points 1 day ago* (last edited 1 day ago)

You have good instincts - that's also what NFPA recommends. This isn't a typical presentation as usually it's one diamond with the worst score of all present chemicals in each category.

You CAN list them individually but it's a pain in the ass for both the building owner and first responders. The whole point is to quickly convey the level of hazards in the building for emergencies. They need to know if they need more information before entering. 2+ diamonds doesn't provide any additional useful data and makes it harder to interpret in a rush.

[–] Devadander@lemmy.world 15 points 2 days ago (1 children)

Why are you assuming the chemicals are mixed together inside the building? Two separate chemicals, two distinct risks.

[–] queermunist@lemmy.ml 3 points 2 days ago (2 children)

But the building, as a whole, pesents the combined risk of both chemicals.

[–] brygphilomena@lemmy.dbzer0.com 18 points 2 days ago (1 children)

First responders need to know that there are two chemicals inside so that they don't stop taking precautions when they encounter the first one.

This is actually my field of work. The composite method queermunist is referencing is the industry best practice for exterior hazard labeling. NFPA diamonds don't always or even often give first responders enough information to enter a building, so there's no utility to multiple diamonds. Responders really don't care how many chemicals are in a facility so much as what they are, and not many facilities actually using chemicals are set up in such a way that your example of encountering one chemical then another would work. They're just everywhere, even during normal operations due to distributed storage and distribution systems.

What these signs do is alert them to the degree of danger inside so they can make decisions, e.g., enter if just flammable, avoid water use, or (most common of all) to act as a reference to ask the building owner more questions before doing anything at all.

[–] Cort@lemmy.world 6 points 2 days ago

They're required to be individually labeled/categorized. And supposed to be on 2 exterior walls, and any doors, and on the containers themselves

[–] Yermaw@lemm.ee 6 points 2 days ago (2 children)

I'm sure they'll be labelled inside too.

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[–] Horse@lemmygrad.ml 5 points 2 days ago (1 children)

i would hope that there would be labels inside the building that would indicate which is which, but who fucking knows with the us lol

[–] NakariLexfortaine@lemm.ee 4 points 2 days ago

They generally have them on the containment units, and if they're used elsewhere, on the pipes/machines carrying/using the chemicals.

Now, if they've been properly replaced since installation is a completely different question. I've seen far too many faded/shredded diamonds on the sides of things.

[–] wolfpack86@lemmy.world 15 points 2 days ago (1 children)

Section 4.2.3.3 of NFPA 704 guides how to handle multiple chemicals.

You can combine the worst of each category into a composite, list each individually, or do a hybrid option.

The posts saying there are two chemicals are true but likely incomplete... There are probably several different chemicals and they decided to go with the hybrid method.

My guess is that they combined the worst rating of everything that doesn't need special handling, and have a stand alone for the chemical that is incompatible with water (or even combined for several chemicals that are incompatible with water).

[–] queermunist@lemmy.ml 2 points 1 day ago* (last edited 1 day ago) (1 children)

That makes sense, but it's still strange because it means in the case of a fire the entire building has to be treated the same anyway because there is something in the building that reacts with water even if its separate.

I guess it is helpful to indicate that there are multiple substances that have different reaction profiles, but it still seems strange to me.

[–] wolfpack86@lemmy.world 2 points 1 day ago

Yeah it's really there to guide how fucked up it can be and not really be mega prescriptive. It's not like quantities are on there, either.

Ideally a fire department shows up, sees the signs and then gets in contact with the building owner to start being more specific about what's ahead of them before they just start dumping a ton of water on the building.

[–] spizzat2@lemm.ee 12 points 2 days ago (1 children)

I'm no expert, so I can't tell for sure, but my guess is that they're storing two different chemicals. The left one looks like it's a non-flammable, extremely hazardous material that shouldn't be exposed to water (maybe an alkali metal, like lithium or sodium). The right one is a hazardous material that is a fire hazard above 93°C (200°F), but otherwise stable (maybe some kind of diesel?)

So... If I had to take a wild guess, diesel and lithium batteries?

[–] GreyEyedGhost@lemmy.ca 5 points 2 days ago

Reading this made me wonder how metallic lithium is stored and, guess what, it's stored in oil. So, which label do you use for a container holding lithium and oil? I'm guessing you need two, one for the lithium and one for the oil. And here we are.

No, I don't think this building is filled with lithium and covered in oil, but I suspect there is more than one container containing metallic lithium covered in oil.

[–] ShellMonkey@lemmy.socdojo.com 13 points 2 days ago

Similar to the markings used on trucks hauling hazardous materials. Might be for the fire dept if the place goes up in flames.

[–] originalucifer@moist.catsweat.com 11 points 2 days ago (1 children)
[–] dohpaz42@lemmy.world 5 points 2 days ago
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