Technical Booklet E Fire Safety·Page 89·Diagram 3.1
Limitations on groups of thermoplastic rooflights and lighting diffusers in suspended ceilings
Groups of Class 3 plastic rooflights and TP(b) thermoplastic rooflights and lighting diffusers must be limited in extent, with a maximum area of 5 m² in any one 5 m × 5 m group and a minimum of 3 m spacing between groups.
Diagram 3.1 Limitations on groups of Class 3 plastic rooflights and TP(b) thermoplastic rooflights and lighting diffusers in suspended ceilings see para 3.14(b), 3.16(b) and Table 3.2 note (1) and (4). 5 m2 is the maximum area of diffuser or rooflight in any one 5 m x 5 m group. 5 m max. spacing (between groups of panels). 3 m min. spacing (between groups of panels).
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