NZS 6806:2010 was prepared by an independent committee facilitated by Standards New Zealand.
The assessment method in NZS 6806 requires consideration of a number of noise mitigation options depending on the scale of a project. These options are subject to an integrated design process, in which the costs and benefits of the mitigation is considered. In some instances the best practicable option is the ‘do- minimum’ design with no specific noise mitigation.
NZS 6806 does not set rigid noise limits but gives categories (A, B and C) of noise criteria, and requires that the Best Practicable Option (BPO) be identified to mitigate road-traffic noise. The upper category (C) provides a backstop against adverse health effects, such as sleep disturbance, by requiring the insulation of houses if the external noise would not be sufficiently reduced using the BPO.
Noise mitigation options are to be assessed, and if practicable, the category A criterion should be achieved. If this is not practicable then mitigation should be assessed against category B. However, if it is still not practicable to comply with categories A or B then mitigation should be implemented to ensure the internal criterion in category C is achieved.
Category |
Criterion |
Altered roads |
New roads |
New road |
A |
Primary |
64 dB |
57 dB |
64 dB |
B |
Secondary |
67 dB |
64 dB |
67 dB |
C |
Internal |
40 dB |
40 dB |
40 dB |
The assessment method in NZS 6806 requires consideration of a number of noise mitigation options depending on the scale of a project. Mitigation options determined using NZS 6806 will typically comprise low-noise road surfaces and noise barriers. If these are not sufficient then building-modification such as mechanical ventilation may be required so windows can remain closed.
NZS 6806 uses several specific terms. A selection of the key terms is provided below, but many have complex definitions and reference to NZS 6806 is essential.
For further information contact environment@nzta.govt.nz.