Abstract: A protective hood jacket adapted to be worn in combination with a protect suit in toxic environments comprises a hood jacket formed of heat-sealable material forming a garment that is hip length and short sleeved. There is a large hump in the rear to accommodate the air cylinder of a self-contained breathing apparatus and to avoid for forward bending. There is a combination closure in the back of the jacket consisting of a metal zipper and a CHLOROPEL zip-loc closure for donning/doffing an air bottle replacement. Vapor leakage is mechanically reduced by two types of seals. The first type encompasses the garment peripheries at the waist and sleeve ends and these seals incorporate cable draw strings and B-lock fasteners allowing for adjustment. The second type constitute internal collars, spaced above the end of the sleeves and waist and around the neck which include elastic webbing providing self-adjustability to fit small, medium and large size personnel.