EU To Germany: Use The Explosive, Toxic Stuff, Or Else

GM was going to use this stuff; the ATS was first in line but they changed their minds allegedly because the compressor produced a different sound that they found objectionable. Phosgene gas is created by high temperature breakdown of the family of refrigerants used in the past. Not sure if a regular fire will do the same thing however. Perhaps there is a chemist out there who will comment. The test that got MB all upset was set by taking a small turbo car with a tight engine compartment, disabling the underhood cooling fan, running the engine hard for an extended period of time, and creating a fault in the refrigerant system to have the refrigerant and OIL spray directly on the superheated turbo. The ensuing fire created the controversy. I am curious just how any refrigerant/oil mix would perform under those conditions...

@golden2husky You're correct that an R12 system tested as MB did would create a similar fireball; when properly atomized, the R12 mineral oil will burn spectacularly. However, what concerned MB was the "hydrogen fluoride" produced when HFO-1234yf burns. This stuff etched the MB windshield, turning it milky white. Here's the reference: http://www.thetruthaboutcars.com/2012/12/environmenatlly-safe-refrigerant-can-blow-up-and-poison-you-if-you-arent-dead-already/ As for burning R12, it may produce phosgene gas, but it can't be much. I have some service manuals from the 1960s that show a leak detector made from a propane torch and a rubber hose; when the hose picked up leaking R12, the torch flame changed color! stuart

@stuart If it's out gassing HF when it burns, damaged windshields are the least of your problems...

golden2husky - - - R12 (dichlorodifluoromethane, "Freon") was the worst of the early group of refrigerants in both environmental impact and potential for phosgene production upon thermal decomposition. However, the conditions for significant amounts of that lethal gas would have to be just right: excess oxygen; > 300-350 deg C; confined space, --- and then you finally get some (Cl)2C=O. Ordinary "open" ventilated car fires would likely be nothing to worry about (from that source anyway). Other cholorfluorocarbon refrigerants are very much less likely to produce phosgene. And R134A (1,1,1,2 tetrafluoroehtane) obviously can't produce any phosgene at all upon decomposition. This is one of these "scare" situations that exceeds the reality of a usual car fire, given the fact that occupants somehow have a desire to get anyway from a burning car! But here is a comment that reviews all this much better than anything I could add: "When a refrigerant is decomposed or burned, the primary products formed are acids: Hydrochloric acid (HCI), if the refrigerant contains chlorine, and hydrofluoric acid (HF), if it contains fluorine. These products are certainly formed when hydrogen is present, such as from the breakdown of oil, water or if the refrigerant has hydrogen attached (like R-22 or R-134a). If oxygen also is present (from air or water), then it's possible to form carbon monoxide, carbon dioxide and various unsaturated carbonyl compounds -- the most notorious of which is phosgene. Being extremely toxic in small amounts, phosgene formation was a real concern when traditional refrigerants (R11, R- 12, R- 113, R- 114) decomposed. Phosgene contains two chlorine atoms and an oxygen atom. It will only form when oxygen is present and only the refrigerants with chlorine attached will produce phosgene (not HFCs). R22 has only one chlorine atom per molecule, so it is extremely difficult, chemically speaking, to get another one attached to form phosgene. Decomposition of R-22 or HFCs may form other carbonyl fluorides, however they are not as toxic as phosgene." ref: http://uk.answers.yahoo.com/question/index?qid=20070327153627AAaDFtw ------------------------

@NMGOM Thanks for the info. I never heard of firefighters being concerned about phosgene gas from a burning car. They seem to have plenty of other things to worry about!

@golden2husky Exactly.

In large part, no. In most countries you would have to show willful negligence to collect at all, and the award would be a tiny fraction of what you would get here. Europeans are big believers in personal responsibility.