Acoustic Testing - Can you rely on it?
Acoustic performance is an important part of a space’s fitness for purpose and the productivity of its intended use. This is especially important in entertainment, recreation, retail, education and office environments.
Currently there are many acoustic products and copies available on the market, but how do you tell whether they are what they claim they are?
To test acoustic test data for validity you need to ensure the following:
1. Performance across all relevant frequencies.
The most common basic measure of acoustic (Reverberation control) performance is NRC.
This measure, a number between 0 and 1 can be briefly described as the proportion of sound that it absorbs and is used by many product suppliers in claims of acoustic performance.
NRC is an average across a range of frequencies and is not a complete picture.
For an acoustic consultant to get a complete picture of a product’s acoustic performance across all frequencies they would need test data for each frequency.
2. Testing to Australian Standards
Sound absorption testing must be done in accordance with Australian Standard AS ISO 354-2006: “Acoustics – Measurement of sound absorption in a reverberation room”*
The measurement results are then rated according to AS ISO 11654-2002: “Acoustics – Rating of sound absorption – Materials and Systems”.
(There is another methodology known as impedance tube testing but this is not as accurate and accepted in the industry to only be used as an indicative guide during product development.)
3. Tests conducted with “As built” framing support, air gaps and conditions.
It is also important that the tests are conducted with framing or support structure and air gaps as the panels will be installed.
*This can only be done in a specially built reverberation room that has been NATA Certified for these specific tests. In the past there were only two of these massive concrete floating rooms in the whole of Australia, one at RMIT in Melbourne and the other at the National Acoustic Laboratories in Sydney. However, NAL has now moved and in 2013 no longer have a reverberation room facility so now all future Acoustic Testing in Australia must be done in Melbourne.
Supawood have invested significantly to secure the most comprehensive range of acoustic test results in Australia, with absorption co-efficients across the full range of frequencies right across our range of products from Supacoustic acoustic panels to Supaslat linear products to Supaslat Maxi beam ceilings.