The blast-proof performance of all electrical machines and electric appliances of QB model blast-proof overhead crane with hook conforms to the prescriptions of GB3836.2～2000 Blast-proof Electrical Apparatus for Explosive Atmosphere Part two: Flameproof Type; the performance of complete machine conforms to the prescriptions of JB/T5897--2006 Blast-proof Bridge Crane. The crane is qualified inspected by inspection unit of blast-proof product which is appointed by the state. The crane has got Certification of Conformity of An Instrument for Explosive Atmosphere. The signs of blast-proof are Exd II BT4 and Exd II CT4 respectively
    The product is applicable to the place in the factory where the capability of transmitting-explosive is no higher than grade II B or II C, and where has mixture of detonating gas which is composed of flammable gas or steam, whose ignition temperature team belongs to T1～T4 team, and air. The applicable danger area is Area 1 or Area 2 (see GB3836.1～2000 for detail) .
    The product shall be operated on ground; it also can be cab-operated as the user needs. The working classis middle.