The ambient temperature and relative temperature of steel structure fire retardant coating construction should meet the requirements of product specification. When there is no requirement in the product manual, the ambient temperature should be between 0- 15℃, the relative temperature should not be greater than 90%, and the air should be circulated. When the wind speed is more than 5m/s, it is not suitable for construction in rainy days or when there is dew on the surface of components. Dust, grease, scale and rust on the surface of the whole component should be removed before painting the fire retardant paint.