2
All unoccupied spaces comply with the indoor ambient noise level targets as detailed in the more rigorous of criteria 2.a or 2.b:
2.a
Indoor ambient noise level targets within national building regulations or other appropriate good practice standards
2.b
Where national building regulations or good practice standards do not exist for the building type or do not provide indoor ambient noise targets, the indoor ambient noise levels comply with 'good practice' criteria levels outlined in Table 20
3
A SQA carries out ambient noise measurements to ensure that the relevant spaces achieve the required levels. Where the measurements identify that spaces do not meet the standards, remedial works are carried out and the measurements repeated to confirm that the levels are achieved prior to handover and occupation.
4
The sound insulation between acoustically sensitive rooms and other occupied areas comply with the privacy index, as detailed in the more rigorous of criteria 4.a or 4.b:
4.a
Sound insulation between acoustically sensitive rooms and other occupied areas comply with targets within national regulations or other appropriate good practice standards
4.b
Where relevant national regulations or good practice standards do not exist for the building type or do not provide sound insulation performance targets, the sound insulation between acoustically sensitive rooms and other occupied areas complies with the following privacy index: Dw + LAeqT > 75. Where privacy is viewed to be critical by the client or design team (e.g. doctor's consulting room, consulting room within a bank) or where the room is adjacent to a noisy space such as a music room, the area should comply with an enhanced privacy index: Dw + LAeqT > 85.
Dw is the weighted sound level difference between the two spaces
LAeqT is the measured indoor ambient noise level in the acoustically sensitive room (for the purposes of awarding design stage credits, the design ambient noise level can be used).
5
The source and receive room sound pressure levels from which Dw is determined are measured in accordance with (EN) ISO 140-4:1998 and rated in accordance with (EN) ISO 717-1:1996. Measurements must be based on finished, but unfurnished rooms, accounting for, and to include the effect of, any carpets and acoustically absorbent ceilings specified.