# Phosgene poisoning
**URL:** https://boards.straightdope.com/t/phosgene-poisoning/928198
**Category:** Miscellaneous and Personal Stuff I Must Share
**Created:** [December 16, 2020, 7:37pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198 "2020-12-16T19:37:45Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@rbroome](https://boards.straightdope.com/u/rbroome)
#### Post date: [December 16, 2020, 7:37pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/1 "2020-12-16T19:37:45Z")
I just learned something new to me. One can suffer phosgene poisoning, as in the poison gas, from a leaking refrigerator! A friend of ours ended up in the emergency room when the refrigerator decided to fail in the worst way possible. It turns out that CFHCs break down into phosgene gas when heated. The frig apparently had an electrical short and that burned the coolant line and the refrigerant. Ouch.
No serious injuries in this case, but people (usually service personnel who didn’t flush out the coolant lines well enough before brazing the pipes) have been killed by this gas.
Yet another thrilling aspect of home ownership!
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### Author:  [@beowulff](https://boards.straightdope.com/u/beowulff)
#### Post date: [December 16, 2020, 7:46pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/2 "2020-12-16T19:46:15Z")
Yeah, that’s probably a 100x less likely way to die than tripping over your dog.
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### Author:  [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)
#### Post date: [December 16, 2020, 8:19pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/3 "2020-12-16T20:19:40Z")
I design industrial control systems for a living, and one of our customers makes phosgene gas. It’s used to make plastics, pesticides, and other stuff, it’s not like folks just buy containers of phosgene at ye ol local hardware store. Phosgene is used in the production of the plastic that eyeglass lenses are made out of, for example.
According to my safety training, phosgene gas smells like freshly cut grass. That smell is a big warning sign if you work in a plant that makes phosgene. A lot of the safety training in a chemical plant boils down to “there’s no such thing as a good siren” and “if a siren goes off, follow the guys in company shirts because they know where the safe spots are” (as an aside, I have also learned that cyanide smells like bitter almonds).
Phosgene was used as a chemical weapon in WWI. Thousands of people died from its use. It’s nasty stuff. People have died in industrial leaks. I wouldn’t expect enough phosgene to be created just from brazing pipes to be fatal, although I can definitely picture it making someone sick. It’s more of a danger in a large fire. The refrigerant in a commercial office air conditioning unit or something like a restaurant freezer can easily create toxic levels of phosgene in a large fire. I don’t have statistics, but I do know that some firefighters have died from this type of phosgene poisoning.
I have heard of refrigerator technicians ending up in the hospital, but I’ve never heard of any actually dying from this type of poisoning. If anyone has a cite for that I’d like to see it.
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### Author:  [@rbroome](https://boards.straightdope.com/u/rbroome)
#### Post date: [December 16, 2020, 9:08pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/4 "2020-12-16T21:08:24Z")
Here is the reference I found. It isn’t much, just a comment in a blog from 2005. See post #5.
> **[Phosgene Gas](https://hvac-talk.com/vbb/showthread.php?79147-Phosgene-Gas)**
>
> The #1 HVACR Community
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### Author:  [@Melbourne](https://boards.straightdope.com/u/Melbourne)
#### Post date: [December 16, 2020, 11:14pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/5 "2020-12-16T23:14:09Z")
> [@engineer\_comp\_geek](#):
>
> I have heard of refrigerator technicians ending up in the hospital
Did you know that you can _detect refrigerant leaks_ by using a brazing torch? The flame color changes as the leaking gas is converted to phosgene …
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### Author:  [@Melbourne](https://boards.straightdope.com/u/Melbourne)
#### Post date: [December 16, 2020, 11:17pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/6 "2020-12-16T23:17:57Z")
> [@engineer\_comp\_geek](#):
>
> “if a siren goes off, follow the guys in company shirts because they know where the safe spots are”
Hey, did you know that radiologists are x-ray opaque? The safest place to stand when an x-ray is taken is – behind the radiologist --. Also, a friend of mine was working in a match factory. When one of the machines caught fire, he headed over towards it to see if he could do anything useful. Then he noticed _everyone else was going the other way_ 🙂
Another friend did some mine work. It was a noisy place: when they had an alarm, they pumped odourant through the ventilation, and … everybody left …
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### Author:  [@Senegoid](https://boards.straightdope.com/u/Senegoid)
#### Post date: [December 17, 2020, 8:37am UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/7 "2020-12-17T08:37:26Z")
> [@Melbourne](#):
>
> Hey, did you know that radiologists are x-ray opaque? The safest place to stand when an x-ray is taken is – behind the radiologist --. Also, a friend of mine was working in a match factory. When one of the machines caught fire, he headed over towards it to see if he could do anything useful. Then he noticed _everyone else was going the other way_ 🙂
This sounds very much like something Derek Lowe would write. [In this excerpt, he describes _chlorine trifluoride_](https://blogs.sciencemag.org/pipeline/archives/2008/02/26/sand_wont_save_you_this_time) :
> [@](#):
>
> It is apparently about the most vigorous fluorinating agent known, and is much more difficult to handle than fluorine gas. That’s one of those statements you don’t get to hear very often, and it should be enough to make any sensible chemist turn around smartly and head down the hall in the other direction.
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### Author:  [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)
#### Post date: [December 17, 2020, 11:19am UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/8 "2020-12-17T11:19:57Z")
> [@engineer\_comp\_geek](#):
>
> (as an aside, I have also learned that cyanide smells like bitter almonds).
I learned that one back in the early 1980s during the **[Tylenol murders](https://en.wikipedia.org/wiki/Chicago_Tylenol_murders)**.
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### Author:  [@Joey\_P](https://boards.straightdope.com/u/Joey_P)
#### Post date: [December 17, 2020, 12:40pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/9 "2020-12-17T12:40:51Z")
Way back in the day when everyone at every business used to smoke indoors, my HVAC guy would always make a point of saying you shouldn’t smoke in the (walk-in) cooler because if there’s any leaks, the refrigerant can get drawn through the cigarette and turn into phosgene gas.
I’m nearly positive I started a thread about it many many years ago asking for confirmatin. I’ll have to try to dig it up later.
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### Author:  [@mixdenny](https://boards.straightdope.com/u/mixdenny)
#### Post date: [December 17, 2020, 4:29pm UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/10 "2020-12-17T16:29:54Z")
> [@beowulff](#):
>
> Yeah, that’s probably a 100x less likely way to die than tripping over your dog.
My best friend from back in my racing days recently died after tripping over his cat. So we’re tied with the phosgene right now.
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### Author:  [@Senegoid](https://boards.straightdope.com/u/Senegoid)
#### Post date: [December 18, 2020, 4:34am UTC](https://boards.straightdope.com/t/phosgene-poisoning/928198/11 "2020-12-18T04:34:05Z")
> [@Machine\_Elf](#):
>
> I learned that one back in the early 1980s during the **[Tylenol murders](https://en.wikipedia.org/wiki/Chicago_Tylenol_murders)**
And I learned that some long time ago from a movie that depicted people being herded into the “showers” at the concentration camps, where someone (maybe a child?) exclaims “it smells like almonds!”