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Design Code for Fire Protection and Smoke Exhaust Skylights for High-Rise Buildings Section 1 General Provisions for Fire Protection and Fire Smoke Exhaust Skylights Natural fire protection and smoke exhaust skylight skylight facilities for exterior windows. 1.2 The fire protection and smoke exhaust skylights and skylights facilities of high-rise buildings should be divided into mechanical fire protection and smoke exhaust skylights and skylights and natural fire protection and smoke exhaust skylights and skylights that can open external windows. 1.3 The following parts of Class I high-rise buildings and Class II high-rise buildings with a building height exceeding 32m shall be equipped with fire protection and smoke exhaust skylights and skylight facilities: (1) Inner walkways with a length exceeding 20m. (2) Rooms with an area exceeding 100m2 and where people often stay or have a lot of combustible materials. (3) Atriums in high-rise buildings and basements where people often stay or where there are many combustible materials. 1.4 Ventilation and air conditioning systems should take fire and smoke prevention measures. 1.5 The wind speed of mechanical pressurized air supply and mechanical fire-fighting smoke exhaust skylights shall comply with the following regulations: (1) When metal air ducts are used, the wind speed shall not be greater than 20m/s. (2) When using air ducts made of non-metallic materials such as concrete with smooth inner surfaces, the air duct should not exceed 15m/s. (3) The wind speed at the air supply outlet should not be greater than 7m/s; the wind speed at the fire-fighting smoke exhaust skylight should not be greater than 10m/s. Section 2 Natural Fire Fighting Smoke Exhaust Skylights Skylights 2.1 Except for first-class public buildings with a building height exceeding 50m and residential buildings with a building height exceeding 100m, the smoke-proof stairwells and front rooms near the exterior walls, fire protection In the front room of the elevator room and the shared front room, natural fire protection and smoke exhaust skylights should be used. 2.2 The window opening area of ??the skylight when using natural fire-fighting smoke exhaust skylights shall comply with the following regulations: (1) The area of ??openable external windows of the smoke-proof stairwell flash room and fire-fighting elevator front room shall not be less than 2.00m2, and the shared front room shall not be less than 2.00m2. Should be less than 3.00m2(2) The total area of ??openable exterior windows in every five floors of smoke-proof stairwells adjacent to the exterior wall should not be less than 2.00m2(3) The area of ??openable exterior windows of inner walkways not exceeding 60m in length should not be less than 2% of the aisle area (4) The area of ??the openable exterior window of a room that requires firefighting and smoke exhaust skylights should not be less than 2% of the area of ??the room. (5) The area of ??openable skylights or high side windows in an atrium with a clearance height less than 12m shall not be less than 5% of the floor area of ??the atrium. 2.3 In the front room of a smoke-proof stairwell or a shared front room, if there are open balconies, alcoves or openable external windows in different directions in the front room for natural fire protection and smoke exhaust, the stairwell does not need to be equipped with smoke prevention measures. 2.4 Fire-fighting and smoke exhaust skylights Skylight windows should be set at the top and should be easily opened. Section 3 Mechanical Smoke Prevention 3.1 The following locations should be equipped with independent mechanical pressurized air supply smoke prevention facilities: (1) Smoke-proof stairwells, fire elevator front rooms or skylights that do not have the conditions for natural fire-fighting smoke exhaust skylights Shared front room. (2) For smoke-proof stairwells that adopt skylights and skylights for natural fire protection and smoke exhaust, their front rooms do not have the conditions for skylights and skylights for natural fire protection and smoke exhaust. (3) Close the refuge floor (room). 3.2 The mechanical pressurized air supply volume of the smoke-proof stairwell and its front room, shared front room and fire stairwell front room of high-rise buildings shall be determined by calculation, or according to the provisions of Table 3.2-1 to Table 3.2-4. When the calculated value is inconsistent with this table, the larger value of the two should be used. Pressurized air supply meter for smoke-proof stairwells (no air supply in the front room) 3.2-1 Pressurized air supply volume of system burden layers (m3/h)