HEGA is an acronym for "High Efficiency Gas Absorption". Originally developed by the British military as a defense against chemical warfare, HEGA is a carbon cloth filter. This carbon cloth has been claimed to be many times more efficient than the granular activated carbon form at adsorption of gaseous pollutants. With its light weight and easy workability, HEGA filters are now used in some residential air purifiers.
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HEGA Wikipedia(Text) CC BY-SA