The invention relates to a combination of a helmet or a protective mask and a respirator that can function under ram pressure. The helmet's chin arch (1) contains a face element (4), a filter (3) and inhalation and exhalation valves (5,6). The air can, for instance, flow through the ...http://www.google.es/patents/US5758639?utm_source=gb-gplus-sharePatente US5758639 - Combination of a helmet and a respiratror and a method for using it
Combination of a helmet and a respiratror and a method for using it
