[NN5I]

I have used 100-175 psi air for blowing out electronics for the last 40 or 50 years. As long as you don't do something obviously stupid, like blasting foil-thin cooling fins or those of air variable capacitors at close range, there's no problem. If you do do something obviously stupid, there's probably no hope for you anyway.

Tektronix used to use, as the first step even before diagnostics, distilled water at rather high pressure to clean out the insides of vacuum-tube oscilloscopes sent in for repair. Then they'd dry'em off with warm compressed air, and about 60% of problems would disappear. Dust causes all sorts of grief.