Fireproof window refers to the window that can meet the requirements of fire resistance stability and fire resistance integrity together with the frame within a certain period of time. When lighting and ventilation are required on the exterior walls of two buildings with insufficient fire separation, or between spaces separated by firewalls, fireproof windows shall be used.  

There are two categories of fireproof windows sold in China: one is fireproof windows that not only maintain integrity within the specified time, but also have thermal insulation function; The other is the fireproof window that maintains integrity within the specified time, but does not have thermal insulation function. In terms of fire protection function, these two types of fire windows can be used for exterior wall windows. Generally, the amount of combustibles on the exterior wall is relatively small. As long as the exterior wall window can maintain integrity and not break under the action of flame or high temperature, the possibility of the external flame igniting the internal objects on the upper floor is very small. Generally, The fireproof window made of Class C fireproof glass and fireproof window frame whose light transmittance will not change with time can meet the requirements of preventing the spread of flame from outside to inside. However, in the following special cases, it is still recommended to use fireproof windows with thermal insulation function.