Skip to main content

Acoustics Testing

Reduction of impact


Danny McCaul
t: +44 (0)161 295 4615

What is impact sound or impact improvement?

Impacts on an object’s surface can set up vibrations within that object, when these vibrations are radiated to the air they produce sound waves. In the case of a building structure this can mean footfalls on the floor above can radiate sound into the room below. Measuring the impact improvement of a floor covering will give a measure of how much less the impact will radiate as sound into the room below when a particular floor covering is used. We measure impact improvement in our large reverberation room.

What is expected of you?

Written descriptions of the samples must be provided prior to testing including mass per unit area and thickness of the sample (preferably prior to quotation); a test report cannot be provided without this information. Usually, you can send the sample to us and we will install it for testing when the large reverberation room is available for use.

impact testing


What do the results look like?

The results will be presented as part of a complete report. A single figure weighted impact improvement value (ΔLW) will be calculated. The reduction values for each 1/3rd octave value will also be calculated. These results will be presented in a manner accordant with the BS EN ISO 717-2 standard; a specimen results sheet is available. Please note the results  are not pass/fail criterion.

What size of sample should I provide?

Three 0.5m x 1.0m samples are required.

What do our customers most often forget when preparing for testing at the laboratory?

If the sample needs to be tested with an underlay don’t forget to include three 0.5m x 1.0m samples of this too.

How long is each test?

The first test is the longest because reverberation times, the background, and bare floor measurements must be made. After calibration the first test should take 1 hour to 1 ¼ hours and subsequent tests should take 30mins.

How many tests can I do in a day?

Provided the installation of the sample doesn’t hold us up too much we should be able to do up to four impact improvement tests in a day. If necessary we can do more than this for an additional charge.
Discounts (multiple tests)

The first test of each day includes calibration and set up of equipment therefore subsequent tests on the same day are cheaper than then first.

When will I get the report? When can I get the results?

We can provide preliminary results on the day of test. The test report will follow in 2-4 weeks after test completion, depending on our workload and the complexity of the test carried out.