GGG-M-125-11A, FEDERAL SPECIFICATION, RESPIRATOR ASSEMBLY: HELMET WITH POWERED AIR-PURIFYING UNIT (PORTABLE BACK-PACK) (20 SEP 1982)

GGG-M-125-11A, FEDERAL SPECIFICATION, RESPIRATOR ASSEMBLY: HELMET WITH POWERED AIR-PURIFYING UNIT (PORTABLE BACK-PACK) (20 SEP 1982)., This specification covers the specific requirements for a protective helmet and hood respirator, with a portable rechargeable battery operated back-pack air-purifying unit, for removing particulate matter larger than 0.3 microns in diameter, and to supply a positive pressure to the wearer of the respirator system.