Technical Booklet E Fire Safety·Page 142·Diagram 5.4
Unprotected areas which may be discounted
Diagram 5.4 shows the specific dimensions and areas of unprotected sections that may be allowed on external walls, with restrictions based on distance from compartment boundaries.
Unprotected area of not more than 1 m² which may consist of two or more smaller areas amounting to not more than 1 m² within an area of 1 m x 1 m; unprotected area of not more than 0.1 m²; external wall of a protected stairway. Dimensional restrictions: 4 m minimum distance; 1.5 m minimum distance; dimension not restricted.
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