Packaging gas

A packaging gas is a gas used to pack sensitive materials in a modified atmosphere. It is usually inert, or of a nature that protects the packaged goods, thus inhibiting reactions such as spoilage. Some may also serve as propellant for aerosols like whipped cream.

For packaging food, various gases are approved. Their E numbers are in parenthesis:
 * argon (E938), used for canned products
 * helium (E939), used for canned products
 * nitrogen (E941)
 * oxygen (E948), used eg. for packaging of vegetables
 * hydrogen (E949)
 * carbon dioxide (E290, also propellant)

Specific kind of packaging gases are aerosol propellants:
 * dichlorodifluoromethane known as CFC (E940), rarely used because of the damage that it does to the ozone layer
 * nitrous oxide (E942), used for aerosol whipped cream canisters (see Nitrous oxide: Aerosol propellant)
 * butane (E943a)
 * isobutane (E943b)
 * propane (E944)