Technical Booklet G Resistance to the Passage of Sound·Page 122·B3.14
Flanking laboratory: indicative impact sound insulation values
When a test construction achieves no more than 58 dB L'nT,w in a flanking laboratory, it indicates the same construction may achieve no more than 62 dB L'nT,w when built in the field.
When a test construction has impact sound insulation no more than 58 dB L'nT,w when measured in a flanking laboratory using the procedure given in Appendix B: B2, this can be taken as indicative that the same construction (i.e. identical in all significant details) may achieve no more than 62 dB L'nT,w when built in the field (see paragraph B3.11).
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