Technical Booklet E Fire Safety·Page 119·Diagram 4.7
Cavity ceiling surface classification
Upper ceiling surfaces must be Class 1 (National) or Class C-s3,d2 (European); lower surfaces must be Class 0 (National) or Class B-s3,d2 or higher (European).
upper ceiling surface – Class 1 (National class) or Class C-s3,d2 (European class)
lower ceiling surface – Class 0 (National class) or Class B-s3,d2 or higher (European class)
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