WEBVTT - Why Shouldn't Compressed Air Canisters Be Shaken?

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<v Speaker 1>Welcome to brain stuff from how stuff Works High brain Stuff,

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<v Speaker 1>Lauren bulk bomb here, whether it's dry shampoo or paint,

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<v Speaker 1>or accustomed to shaking aerosol canisters before we spray them.

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<v Speaker 1>So it's only natural that when we pick up a

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<v Speaker 1>canister of compressed air to clean a keyboard, we also

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<v Speaker 1>want to shake the can even if it's label clearly

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<v Speaker 1>says do not shake. But is this force of habit

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<v Speaker 1>potentially harmful? In a word, yeah, compressed air canisters are

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<v Speaker 1>not really canned air. Rather, these canisters contain a compressed

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<v Speaker 1>liquefied gas that propels its own vapors through a nozzle.

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<v Speaker 1>Most of the time, the liquefied gas is one of

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<v Speaker 1>two types. One is die fluoro ethane or HFC one

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<v Speaker 1>two A, which is found in canisters marketed for computers

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<v Speaker 1>and electronic equipment, and incidentally is also known as free

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<v Speaker 1>on that same gas that helps make refrigerators and car

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<v Speaker 1>air conditioners cool. The other type of gas is tetrafluoro

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<v Speaker 1>ethane or HFC one D four A, which is recommended

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<v Speaker 1>for use when flammability might be an issue, such as

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<v Speaker 1>with hot surfaces or spark producing equipment. However, some types

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<v Speaker 1>of canned air may also contain butane, the same liquefied

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<v Speaker 1>gas found in cigarette lighters. According to three M, which

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<v Speaker 1>manufactures and cells compressed air canisters for dust removal, shaking

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<v Speaker 1>or tilting the can it may result in propelled liquid

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<v Speaker 1>instead of vapor. If this happens, the liquid may come

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<v Speaker 1>into contact with skinner eyes and cause frost bite because

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<v Speaker 1>the chemical will freeze your skin at room temperature. If

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<v Speaker 1>this happens, medical attention may be warranted. But first three

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<v Speaker 1>M recommends washing affected areas of skinless soap and water,

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<v Speaker 1>or flushing eyes with copious amounts of water. But what

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<v Speaker 1>about all those other air sel canisters that do recommend

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<v Speaker 1>shaking before use. Unlike the liquefied gas and canned air

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<v Speaker 1>that propels itself out through the nozzle, everything from dry

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<v Speaker 1>shampoo to spray paint requires a little mixing. The product

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<v Speaker 1>inside the can separates into layers and must be shaken

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<v Speaker 1>to mix with the propellant before use, otherwise the propellant

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<v Speaker 1>would come out. Today's episode was written by Laurie L.

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<v Speaker 1>Dove and produced by Tyler Clang. For more on this

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<v Speaker 1>and lots of other expansive topics, visit our home planet,

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<v Speaker 1>how stuff Works dot com,