Wind farm noise – Revised draft Standard available now for public comment
25 February 2009
Standards New Zealand invites public comment on draft Standard DZ 6808 Acoustics – Wind Farm Noise.
The purpose of this Standard is to provide suitable methods for the prediction, measurement and assessment of sound from wind turbines for use in both wind farm development and local authority planning procedures. This Standard also provides guidance on the limits of acceptability for sound received at noise sensitive locations emitted from wind farms containing one or more wind turbines.
DZ 6808 is a revision of NZS 6808:1998 Acoustics – The assessment and measurement of sound from wind turbine generators. The 1998 version was written prior to significant wind farm development in New Zealand. The basic methodology proved robust, but experience and research over the following decade brought to light numerous refinements and enhancements, which are now addressed in the revised draft.
The terminology and format of the Standard have been updated to align with the 2008 editions of NZS 6801:2008 Acoustics – Measurement of environmental sound, and NZS 6802:2008 Acoustics – Environmental noise. This includes adopting L90 in place of L95 as a measure of sound levels.
The original recommended noise limits are retained, but are added to by provision for a more stringent secondary noise limit where justified by particular local circumstances. The simple prediction method in the 1998 version has been removed, and replaced by methods using octave-band calculations and which account for a wider range of factors influencing sound propagation. Measurement procedures have been clarified and wind speeds are now referenced to the wind turbine hub-height.
Standards New Zealand invites comments on the draft Standard up to 30 April 2009. The technical committee that prepared the draft Standard will then consider each public comment received and reach consensus on any changes that may be necessary. The revised Standard is expected to be published in October 2009.
The draft Standard is available for public comment for a period of two months, ending 30 April 2009. You can download a free copy of the draft, and explanatory notes for providing comments at http://shop.standards.co.nz/goto?id=97, or visit www.standards.co.nz, click on the ‘Public comment' tab and select DZ 6808.
Background to drafting a Standard, and the public consultation procedure
New Zealand Standards are agreed specifications for products, processes, services, or performance. They are flexible, non-statutory instruments that help to ensure a consistent approach towards achieving desired outcomes. The development of a Standard involves a committee of experts on the topic applying their knowledge and experience in a consensus-based process, and includes opportunity for the public to comment on the committee's proposals.
Expert committees comprise a balanced representation from relevant industry groups, professional bodies, central and local government agencies, and community groups who bring a range of technical and other relevant expertise to the table. In the case of DZ 6808, committee members include experts in the field of acoustics. The committee has met on several occasions since being established in July 2008 to review the latest research on sound generated by wind turbines, as well as methods of measuring and predicting wind turbine sound, and assessing its effects. Having drafted a number of technical changes to the existing Standard, the committee now seeks the views of interested parties on those changes and any other comments that will help to produce a robust New Zealand Standard.
The public comment procedure is a requirement of the Standards Act 1988. It is a way of ensuring that the draft Standard is not only technically robust, but that it also meets the needs of those who will use it, including local government and others involved in resource management decision-making.
Once the public comment period closes, all submissions are collated by Standards New Zealand and circulated to the committee for their review. The procedure improves the quality of a Standard by allowing the committee to consider any new information, discuss issues or alternative solutions and to assist the committee in reaching consensus.
When the committee reaches final agreement on the content of the Standard, it is submitted to the Standards Council for formal approval (in accordance with the requirements of the Standards Act 1988) prior to its publication as a New Zealand Standard.
About Standards New Zealand
Standards New Zealand is the operating arm of the Standards Council, and part of New Zealand's standards and conformance infrastructure. Standards New Zealand is an autonomous Crown entity responsible for managing the development and distribution of Standards across a range of sectors nationally.
Standards New Zealand is a self-funded, not-for-profit organisation, relying on revenue primarily from contracts with sponsors to develop Standards, and from sales of Standards publications. Our independence helps us facilitate a cross-section of stakeholders' contributions to the development of Standards, and ensure that each Standard meets the needs of end users.
Get the latest Standards news at www.standards.co.nz/touchstone