BACK PACK INSTRUMENT

PROBLEM TO BE SOLVED: To provide a respirator back pack instrument in which the burden to a mounting person's body can be decreased as possible when a mounting person takes a posture that inclines forward.SOLUTION: A respirator back pack instrument 10 includes: a back plate 11 that is used being disposed on the back of a human body, and to which a pressure container 2 is detachably attached, and that is the back plate 11 that has an upper end 11a that is arranged to face the back when disposed on the back of a human body, and a lower end 11c arranged to face the bottom of the back; a leaf spring part 26 having flexibility, and disposed to the back plate 11 that is the leaf spring part 26 in which a one end part 26a in a longitudinal direction continues to the back plate 11 and that is disposed to extend from the upper end 11a of the back plate 11 to the lower end 11c; a pair of back pack bands 12 that have both ends attached to the back plate 11 and are used to be mounted to the shoulder of a human body; and a waist belt 13 that is attached to the other end 26b in the longitudinal direction in the leaf spring part 26 and is used to be mounted to the waist of a human body.