What is in air duster (canned air)?

Most aerosol duster contains a refrigerant/propellant that cannot be considered “air”. As a matter of fact, breathing too much of these vapors can lead to negative health effects. Compressed Air Duster is most commonly filled with the following propellants: HFC-134a, HFC-152a, HFO-1234ze, CO2, and DME. Refer to the TDS (tech data sheet) or SDS (safety data sheet) for more specifics.