Davoud wrote:

Robert Lazar:
Thanks for the advice, but how does one know which ones do not contain
propellants?

Another thing to remember when using canned air is to only use shorts
blasts of air. If you use long blasts, your going to spew out
propellent, and that stuff leaves a film and can freeze what ever it's
sprayed on. I use canned air to clean my optics. A few short blasts of
air, followed by a light brushing with my Lens Pen and then a few more
light blasts of air. If that don't remove what ever, then It stays
untill I do my yearly cleaning. Another thing to remember when using
canned air is if the can starts feeling cold, quit using it. Put it
down and wait untill it warms up before using it again. On a side note
canned air contains no "air" as in what we breath. At one time canned
air was just a can of freon with a nozzle on it but freon is banned so
now canned air is a mixture of petroleum hydrocarbons and
tetraflouroethane, or basicly propane. Makes one hell of a blow torch!
If you want something with no propellants, get a duster bulb from the
photo store, or get an air compresser with a air drier attached (with
at least 15 foot of hose between the compresser and drier) and you
will have all the canned air you will ever need!
Roger