Hearing Protectors

We are capable of measuring the performance of hearing protectors to BS EN ISO 4869-1:2018.

This testing requires a silent and no reflections of sound, and is therefore performed in our anechoic test chamber. Test subjects are brought into the chamber and the lower threshold of their hearing is determined with and without the hearing protector occluding the ear. The attenuation values provided for the hearing protector are, then, precisely the difference between the lowest audible sound levels recorded with the hearing protector in place and those recorded with the ears unoccluded.

What is expected of you for a hearing protector performance test?

Earmuff style hearing protectors

If the hearing protector is a single-size, 4 samples are required. If the hearing protector is manufactured in multiple sizes, one sample of each size is required and the manufacturer’s instructions will be followed to select the best fit for each subject. If there are less than 4 sizes, supply additional samples of the most common size to make up 4 samples total. Instructions for fitting the hearing protection are required also.

In-ear or earplug style hearing protectors

For hygiene purposes, the number of in-ear hearing protector samples required corresponds to the number of test subjects. Although the final results are presented as an average derived from exactly 16 subjects, additional subjects are included to account for variability in the data; consequently, a minimum of 20 samples is required. If the hearing protector is available in multiple sizes, at least 20 samples per size must be provided.

How many hearing protector models can be tested at once?

For each test subject, up to 2 hearing protector types may be tested per test session. Multiple configurations of the same hearing protector (i.e. active / passive, or headband worn over-head / behind-head) also require separate test sessions and hence are counted as separate ‘types’ for this testing. This is due to time restraints for subjects in the anechoic chamber, as after 3 threshold determination tests have been completed, test fatigue may become significant and effect test results. However, by broadening the amount of subjects in the panel, we may test more hearing protector types within the testing period.

What do the results look like?

The results will be presented as part of a complete report. A results table will provide the individual attenuations of each test subject included in the final results calculations, alongside the mean attenuation at each frequency band, the HML values, SNR value, and a graph of the mean attenuation values.

Can I be present during the testing?

If you would like to be present during the testing (or send a representative) to observe the test or to assist with fitting / configuring the hearing protectors to specific modes, it is possible for you to attend the laboratory for part or all of the testing as you require.

How long does the testing take?

Depending on the number of types of hearing protectors to be tested, the time can vary. For one or two hearing protector types, the threshold testing alone can often be conducted over the course of a single week (not including pre-testing for the subjects to check for functionally suitable hearing for the test, and to prove that they are capable of completing the threshold determination test in the anechoic chamber). For more than two hearing protector types, the testing may take longer, perhaps stretching into multiple weeks.

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

We can provide some preliminary results during and at the close of testing, although depending on later review of the full set of results, the final values may be liable to change. The report will follow in 2-4 weeks after test completion, depending on the workload and number of hearing protector types tested.