| http://www.w3.org/ns/prov#value | - A gas filter (preferably a smoke filter) comprises at least one gas filter element (preferably a smoke filter element) comprising a porous retentive element, i.e., at least one porous medium that retains at least one undesirable material such as at least one of microorganisms (e.g., bacteria), viruses, cells, body fluids, particulates, aerosols and liquid droplets, and allows at least a portion of
|
