How long is the duration of fire resistance that fireproof window of level B can endure?
The duration of fire resistance: fireproof window of level A shall not be less than 1.5h, while level B shall not be less than 1.0h. The frame of both fire proof windows A and B are made of steel, and the glass, not less than 26mm, is composite insulation fireproof glass. Monolithic fireproof glass window is neither B fire proof window nor A fire proof window, but non insulated fire proof window.
Level B refers to the fire resistance rating and different hours in fireproofing of the fireproof window. Fireproof window of level A can endure fire for 1.5 hours while level B, 1.2 hours
Fire proof window of level B is the fire proof window whose duration of fire resistance is not less than 1 hour. Technical requirements: One, Materials and fittings (1) the frame of windows draw on steel or wood frames which have certain intensity and are able to ensure the integrity and stability of components. (2) Steel frame and layering can use galvanized steel or stainless steel plate. Its selection criteria shall be in line with provisions 5.1 of GB12955< steel fire door general technical conditions >. (4) The internal fillings of steel, wood frames should use non combustible materials. (5) Fire proof windows can opt for qualified products without affecting the performance of fire proof window. Light transmittance of glass shall not be less than 75% of the same layer of ordinary flat glass. (6)The sealing material between the frame and the fireproof glass should adopt the nonflammable materials, functioning as the fire blocker. (7)Hardware fittings should be tested for qualified products.
