Technical Booklet E Fire Safety·Page 153·5.23
Thermoplastic materials and unwired glass in rooflights
Thermoplastic materials that cannot be designated under BS 476 Part 3 may be used in rooflights if they meet paragraph 3.5 requirements. Unwired glass at least 4 mm thick is deemed to have AA (National) or BROOF(t4) (European) classification.
Where a thermoplastic material cannot be given a designation when tested to BS 476: Part 3 it may be used as a rooflight provided that it can be classified under paragraph 3.5 and is used in accordance with paragraph 5.25. Where unwired glass, not less than 4 mm thick, is used in a rooflight it should be regarded as having an AA (National class) or BROOF(t4) (European class) designation.
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