I read all about those solvents, and I am surprised that no-one has yet mentioned MEK (Methyl Ethyl Ketone). I used it long before it was banned from Manufacturing Floor. Mostly was to dissolve epoxy packaging on IC befo= re doing a die inspection with electron microscope. Also used to dissolve pott= ing compound for some very critical repairs. That was a real nasty solvent, but we used good precautions like gloves, masks and vented hoods above test area. Just another $0.02, Jean-Paul N1JPL > On Dec 8, 2017, at 7:31 AM, Sean Breheny wrote: >=20 > Bunny suits?! That seems a bit over-the-top unless this was an applicatio= n > where you were spraying large quantities (several liters) into the air. >=20 > I obviously have not done independent research on this - I am only going = by > what I've read in MSDS and other published sources that I read before usi= ng > these chemicals. The US Centers for Disease Control lists the IDLH > (Immediately Dangerous to Life or Health) threshold at 500ppm for both > benzene and toluene but they allow up to 100ppm permissible exposure leve= l > in the workplace for toluene but only 1 ppm for benzene. They also do not > mention any risk of cancer for toluene but they do for benzene. So, I'm n= ot > saying that toluene is just dandy and no precautions are needed, but rath= er > that it is considerably safer than its "parent" molecule benzene for > long-term exposure. >=20 > I also just learned that toluene is a significant risk to pregnant women > with regard to possible miscarriage so I guess it can be very nasty for > some people. >=20 > Sean >=20 >=20 > On Fri, Dec 8, 2017 at 4:13 AM, wrote: >=20 >>>=20 >>> Toluene is also not all that nasty. It is methylbenzene but the methyl >> group >>> seems to prevent most of the carcinogenic action. Maximum safe short-te= rm >>> dose is less than acetone/isopropanol. >>>=20 >>=20 >> Well, that doesn't equate to the hoops we had to jump through to use a >> toluene based conformal coat on our PCBs. A suitable booth with high vol= ume >> air extraction and use of full bunny suits while handling it. >>=20 >>=20 >>=20 >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >>=20 > --=20 > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist Just my $0.02, Jean-Paul N1JPL --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .