The firefighter shown is wearing an SCBA (Self contained breathing apparatus). This is an essential part of a firefighters gear. It allows him to enter hazardous environments and still breathe safe air.
Self-contained breathing apparatus - Wikipedia, the free encyclopedia
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Gear like Hawk wears in IGNITED, a novel by Suzannah Daniels. www.SuzannahDaniels.com Self-contained breathing apparatus - Wikipedia, the free encyclopedia
Self Contained Breathing Apparatus
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Fireman stows a self-contained breathing apparatus in a locker Canvas Art - Stocktrek Images (23 x 35)