Welcome to brain stuff from how stuff Works High brain Stuff, Lauren bulk bomb here, whether it's dry shampoo or paint, or accustomed to shaking aerosol canisters before we spray them. So it's only natural that when we pick up a canister of compressed air to clean a keyboard, we also want to shake the can even if it's label clearly says do not shake. But is this force of habit potentially harmful? In a word, yeah, compressed air canisters are
not really canned air. Rather, these canisters contain a compressed liquefied gas that propels its own vapors through a nozzle. Most of the time, the liquefied gas is one of two types. One is die fluoro ethane or HFC one two A, which is found in canisters marketed for computers and electronic equipment, and incidentally is also known as free on that same gas that helps make refrigerators and car
air conditioners cool. The other type of gas is tetrafluoro ethane or HFC one D four A, which is recommended for use when flammability might be an issue, such as with hot surfaces or spark producing equipment. However, some types of canned air may also contain butane, the same liquefied gas found in cigarette lighters. According to three M, which manufactures and cells compressed air canisters for dust removal, shaking or tilting the can it may result in propelled liquid
instead of vapor. If this happens, the liquid may come into contact with skinner eyes and cause frost bite because the chemical will freeze your skin at room temperature. If this happens, medical attention may be warranted. But first three M recommends washing affected areas of skinless soap and water, or flushing eyes with copious amounts of water. But what about all those other air sel canisters that do recommend
shaking before use. Unlike the liquefied gas and canned air that propels itself out through the nozzle, everything from dry shampoo to spray paint requires a little mixing. The product inside the can separates into layers and must be shaken to mix with the propellant before use, otherwise the propellant would come out. Today's episode was written by Laurie L. Dove and produced by Tyler Clang. For more on this and lots of other expansive topics, visit our home planet, how stuff Works dot com,