Workshop warning

David Morton

Lifetime Supporter
My grandfather was poisoned this and Mustard gas in WW1 - He was an invalid for the rest of his life. Phosgene gas is COCl2
Adventitious occurrence

Upon ultraviolet radiation in the presence of oxygen, chloroform slowly converts into phosgene via a radical reaction. To suppress this photodegradation, chloroform is often stored in brown-tinted glass containers. Chlorinated compounds used to remove oils from metals may also react under the UV created during arc welding to produce phosgene.
I bet it doesn't say that on the can. I have some of it in my garage - thank you for the warning Simon.
After many years of exposure to "brake clean" I have become allergic to it. Carb cleaners seem to be OK, but brake cleaners will have an effect on me within minutes of slowed ability to think through problems and a lack of concentration. In short, ANY exposure, even being in a shop where a couple squirts are sprayed and I just get a whiff of it, has the effect of about 4-5 beers. Sounds good, huh? It's not. Especially when driving and not being able to concentrate. It can last anywhere from a few hours to days depending on the amount of exposure.

I recommend that you use as little brake cleaning fluids as possible.


Lifetime Supporter
When I was an undergrad getting my chemistry degree I did a fractional distillation with a trace amount of phosgene byproduct. It was in a two man lab under a fume hood. The column had a hairline crack and some of the the phosgene dissipated into the lab. I started to feel really crappy so I closed the hood and sealed the door. It dissipated shortly there after. Definitely not a compound you want to be around. Be carefull out there! :freak::freak::freak:
Hmmm - thanks for that Simon. I must admit to using brake cleaner a lot and will definately think about how appropriate the application is in future..

Good find! :thumbsup:
Yikes! I just read the label on my can of Kleen-Flo brake clean and you're right Davd, nothing about reactions with heat. Thanks Simon.


Gulf GT40
Lifetime Supporter
Does the brake cleaner need to contain Cholorinated Stuff, most of the cans on my self have only the good old petrolum distillates listed, but not sure if that is the bad stuff mentioned (cholorinated or not). Also I think the wikipedia has more information on mustard gas as well as phosgene.

I can tell you that when you bulk recycle, in other words call up a truck to come get your drums of used oil, they stick a sniffer into the drums and the word from the service guy is that if the drum contains any chlorinated substances it is considered hazardous waste and costs more than $400 a drum to have them take away. No chlorinated substances equals "no problem".
FYI, use non chlorinated brake cleaner. It's readily available, simply read the labels.
I keep the chlorinated version away from the shop just in case.
Welding or open flame around certain chemicals can do alot of damage. The welding of galvanized metal for one. Certain sealers and plastics contain Isocynates and cutting fluids chromeuim and other compounds. Most post WHIMIS-MSDS sheets for their products on the web. If you are not sure wear a good resperator. I would rather be safe than sorry. Good post Simon.
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I have a Miller 180 mig welder and a aluminum spool gun for the mig that uses straight argon, that's scary are hell. I printed it up and gave it to the other shops in my complex. Thank you very much!
Good Start Al,
I would take it a step further. I watched a bodyshop burn in Toronto yesterday on the news. It was the second time in two years. There will be a few people out of work and I don't know if it will open again. If you guys that have shops just follow some of the simple WHIMIS guidelines you will be safely in buisiness a long time.

First thing I would do Al is go through the shop and do a list of everything you use. I would do up a couple MSDS binders. One for your office and one for the shop floor. They are usually yellow three ring binders.

Secondly I would have your employees go through them every six months and sign off that they read them. One it shows that you care and some of the people you guys employ are highly skilled and hard to replace.

Thirdly, the safe storage and labeling of materials. Most stuff can be stored in a yellow double door cabinet. If you buy in bulk you print up and relabel on to approved containers for use on the shop floor.

By doing this Al your Insurance rates would be lower for your building and workmans comp rates for your employees.
Here is a site to give you all the info you need. Sorry I put a extra " I " in the acronym.
It's " WHMIS". The Province of Ontario has some of the strictest rules. The courses are general and reconized under "NATO". Your state may have some type of training also. This will give some guidelines.