<P> Global warming: Difluoroethane (HFC - 152a), trifluoroethane (HFC - 143a), and completely non-flammable tetrafluoroethane (HFC - 134a) are potent greenhouse gases . According to the Intergovernmental Panel on Climate Change (IPCC), the global warming potential (GWP) of HFC - 152a, HFC - 143a, and HFC - 134a are 124, 4470, and 1430, respectively . GWP refers to global warming effect in comparison to CO for unit mass . 1 kg of HFC - 152a is equivalent to 124 kg of CO </P> <P> Ozone layer depletion: Gas dusters sold in many countries are ozone safe as they use "zero ODP" (zero ozone depletion potential) gases; tetrafluoroethane, for example, has insignificant ODP . This is a separate issue from the global warming concern . </P> <P> True "air dusters" using ordinary air are also available in the market . These typically have much shorter run times than a chemical duster, but are readily refillable . Both hand pump and electric compressor models have been marketed . The maximum pressure for an aerosol can is typically 10 bar (145 psi) at 20 C (68 F). Therefore, a fully compressed air duster will exhaust air about 10 times the can volume . Recently electronic versions which only use air have become viable alternatives that are preferred by many large corporations due to the fact that they contain no hazardous chemicals, are safe for the environment, do not freeze and they cannot be abused by addicts looking to get high . The leading plug - in alternatives are made by DataVac and Airrow and the leading cordless alternative is made by Canless Air System . </P>

How much psi is in a can of compressed air
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