Outdoor steel structure fire ladder is a tool for firefighters to fire fighting, rescue or surmount obstacles. As the main component of vertical connection in building space, the staircase should be clearly positioned to guide the flow of people, and should fully consider its beautiful appearance, smooth flow of people, comfortable walking, strong combination, fire safety, and also meet the requirements of construction and economic conditions.
In the design of outdoor steel fire staircase, the width requirements of different staircase design are also different. The minimum net width of the ladder is determined according to comprehensive factors such as operation requirements, modulus standards and fire protection regulations. It should be noted that the minimum net width of the six-storey and below-six-storey residential staircase is set at 1m.
The width standard in the design of outdoor steel fire staircase is due to:
1. In the past, in order to meet the requirements of fire protection code, the minimum width of staircase section was 1.10m, and 2.70m or 2.60M (not conforming to the 3-model) open staircase was generally used. At present, apartment building tends to have two sets of staircases and two sets of service suites, and the corresponding staircase area can also be reduced. For example, 2.40M open staircases can be used to increase the usage area by about 1m per set, while 2.40M open staircases and staircases in brick-concrete residence can be used. The width can only be about 1 m.
2. 2.40m bays conform to three modes, and can be coordinated with other parameters of three modes into a series. There is no half modulus in the plane layout. The expanded modulus series can be formed with 3.60M and other parameters, which is conducive to reducing components and industrializing production. The plane layout is also more applicable and flexible.
3. It is common to use 2.40M open stairwell in surveys. According to the analysis, 2.40M can meet the requirements as long as the width of stairwell platform can carry furniture.
4. Referring to the relevant norms at home and abroad, and in coordination with the Ministry of Public Security, in the Code for Fire Protection in Architectural Design, it is stipulated that the minimum net width of an evacuation staircase with a balustrade on one side of a six-storey apartment should not be less than 1 m, but that of a seven-storey apartment or all corridor-type and tower-type apartments should be 1.10 M.