Technical Booklet E Fire Safety·Page 42·2.19
Glazing in existing stairway enclosure
Any glazing in the enclosure of an existing stairway (other than to bathrooms or sanitary accommodation) must be fire-resisting.
Any glazing (whether new or existing) in the enclosure of the existing stairway, other than to a bathroom or sanitary accommodation, should be fire-resisting. (See Tables 2.8, 4.1 and 4.2.)
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