[DeTomaso] You must read this if you use brake cleaner..

[JDeRyke at aol.com]

Besides what Wiki says about carbon tetrachloride as a dangerous brake 
cleaner or its earlier use as a dry-cleaning solvent, phosgene can be generated 
from other chlorinated solvents if they're too close to electric arcs. I 
mentioned afew years ago about a couple of welders at my work that got phosgene 
poisoning and passed out from the combination of a degreaser tank full of 
trichloro-ethylene, an arc welder working inside a tank and a ventillating 
fan pointed just the right direction to blow fumes inside. I suspect that 
dichloro- and tetra-chloro-ethylene ('carbon tet') solvents would also react 
this way in a strong electric arc. 
The biggest problem in the cases above turned out to be two high-powered 
doctors that couldn't diagnose the problem- they were far too young to have 
experience with toxic WW1 gasses! That tells me that-   at least in the San 
Francisco Bay Area of California- the malady is rare. Fortunately, head-aches 
were the only remaining problem for the two welders after a good night's 
sleep. FWIW- J Deryke