Outgassing

Outgassing (sometimes called "Offgassing," particularly when in reference to indoor air quality) is the slow release of a gas that was trapped, frozen, absorbed or adsorbed in some material. It can include sublimation and evaporation which are phase transitions of a substance into a gas, as well as desorption, seepage from cracks or internal volumes and gaseous products of slow chemical reactions. Boiling is generally thought of as a separate phenomenon from outgassing because it occurs much more rapidly.
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the release of gases or vapors by a material over time.

DEGASSANDO. DEGASSANDOSI