Those diamonds indicate what chemical hazards are inside the building, for fire and rescue operations.
this post was submitted on 24 Apr 2025
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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.
So... Bring my HEV suit and crowbar?
They're waiting for you, OP, in the test. Chamberrrr.
OP doesn't need to hear this. OP's a highly trained professional.
Depends, are you in the tank today?
What's interesting is they could have made one compound NFPA diamond that encompasses the worst ratings of everything in the building instead of two individual diamonds. The primary intent of these on buildings is to inform first responders of what they might be rushing into.
One diamond might give conflicting or incorrect info if there's several things that would react to logically correct answers when firefighting. Last thing you need is to start a reaction when everything is already on fire because while it lists one reactant, it supercedes another reactant that would have been displayed on a secondary diamond.
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 isnβt 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 thereβs a fire at the warehouse, this tells the responding crew βhey just so you know, thereβs some nasty shit in here. One presents a severe health hazard, becomes potentially explosive when heated, and reacts with waterβ¦ But at least it isnβt 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.β
100% correct answer.
Here's my favourite warning, can you guess what it is?
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 thatβs 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.
I think "Danger" might be putting it lightly...
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.
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
Angry water.
Yeah it basically is, also while it's not flammable itself, it makes almost everything it touches ignite. Even the very unburnable things
https://www.science.org/content/blog-post/things-i-won-t-work-dioxygen-difluoride
Probably related to this, very fun column to read.
Seems like it would definitely not have a 0 in red?
But it was a great read and I'm glad you posted it.
Edit: lol I dumb
Oxidizers aren't typically flammable themselves and only react with fuels.
It makes most things it touches flammable but won't ignite by itself
404 not found
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.
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.
Similar to the markings used on trucks hauling hazardous materials. Might be for the fire dept if the place goes up in flames.
Thank you!
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.