[sdiy] Careful with that old high-proof IPA

[Eric Brombaugh]

Hey folks,

As electronics hobbyists a lot of us will have isopropyl alcohol (IPA) 
around for cleaning circuits and mechanisms. It's come to my attention 
that anhydrous (>99%) IPA left standing for more than a few months is 
prone to forming peroxide crystals that are unstable and potentially 
explosive. Dilute IPA such as what you'd buy at the drug store (70%-90%) 
is safe, but the jug I got at the hardware store is 99% so be aware of 
what you've got lurking in the cupboard. I checked my stash and poured 
in some distilled water just to prevent worries.

More info on that here:
http://www.sciencemadness.org/talk/viewthread.php?tid=21495

Eric