DongNan Elevator Co., Ltdescalator front room should be set up in the fire elevator, and its area: residential buildings should not be less than 4.50m^2. Other buildings should not be less than 6.00m^2. When the front room is shared with the smoke-proof staircase, its area: residential buildings should not be less than 6.00m^2, and other buildings should not be less than 10m^2.