why is air duster not just a canister of compressed air?

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Would it not achieve the same purpose by using high pressure air to clear small debris from electronics? Is there some reason this is impossible? Also what benefits does air duster gain performance-wise by using such a dangerous chemical?

In: Engineering

4 Answers

Anonymous 0 Comments

In order to create a notable amount of compressed air, you really want to be able to store the contents at a high enough pressure that it condenses to a liquid. A small amount of liquid can become a very large volume when given room to expand.

At room temperature, an equilibrium between liquid and gaseous oxygen is very difficult to maintain, typically requiring a vaccum insulated container and a pressure relief value to ensure the contents don’t reach too high of a pressure/temperature.

Refrigerants are much easier to store, as the transition from a liquid to a gas at room temperature occurs moderately close to atmospheric conditions.

Anonymous 0 Comments

Because it lets you store a huge volume of gas as a liquid, which you can’t do with air.

The chemical in air dusters can be easily compressed into a liquid with only a reasonably small amount of pressure. It’s like how lighters are filled with liquid butane. [In the clear ones you can even see the liquid inside](https://www.qualityimprint.com/cdn/shop/products/Q177711-transparent-green-lighters-with-logo-3_grande.jpg?v=1547584685). When you open the nozzle some gas comes out, and a tiny bit of the liquid boils until the pressure is restored.

The advantage is that liquids are hundreds of times denser than gases, can be even 1000x or more. That means the air duster can hold like 1000x more volume of gas this way vs if it was pressurized air. With pressurized air it would have to be a heavy thick steel tank at hundreds of PSI and you still wouldn’t get anywhere near as much gas vs the chemical they use where a whole room volume of gas can be easy compressed into a small canister of liquid at less than 50 PSI.

**TLDR:** The chemical isn’t that dangerous, compared to the downsides of a compressed air can that would be heavy, a potential pressure bomb at hundreds of PSI, *and* also run out in about 30 seconds of spraying.

Bonus: The propane in BBQ tanks is pressurized into a liquid too. Once again, by using propane as the fuel this lets you store a gigantic volume of gas in a small volume and at a much safer lower pressure.

Anonymous 0 Comments

Because it would last a few squirts and be empty if it was a can of air because it’s still stored as a gas. That’s why you put a liquid with a low boiling point in there.

Anonymous 0 Comments

For the same quantity of gas expended the container would have to be like 9000psi. To those who could afford it several would be killed. It’s completely impractical.