How to calculate the area of a fire door with glass

The window glass on the fire door cannot be made as large as you want. There are strict regulations in this respect. The area of the fire glass in a glass fire door exceeds 15% (referring to the glass inlaid with a single door leaf compared with the door leaf), and does not exceed At 30%, it is regarded as a different unit. The area of fireproof glass with glass fireproof door exceeds 15%, and cannot be classified as the same unit with the area of fireproof glass less than or equal to 15% of the door area. The area of fireproof glass reaches or exceeds 30% of the area of the fireproof door leaf as a glass fireproof door.