Test and log the results of individual employees’ earplugs

For the first time you are able to quantify and track the performance of hearing protection equipment, by conducting a function test that generates a corresponding Personal Attenuation Rating (PAR).

This will become increasingly important as insurance companies demand greater corporate protection from industrial injury claims made as a result of noise-induced hearing loss.

The SonoLab Noise Attenuation Testing Programme enables an employer to test SonoLab Instant Fit Custom Moulded Earplugs once they are made, by inserting a microphone into the plug and connecting it to a speaker.

When the speaker emits a ‘white noise’ sound across seven frequency ranges, the software reads the noise levels both inside and outside the ear, and calculates the Personal Attenuation Rating (PAR).

As every ear canal is unique, there are different readings for different users. Individual user information is then translated on to a PDF document to create an accredited certificate that can be stored on the user’s profile in the workplace.

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The equipment comprises:

  • A unique dual microphone insert to measure sound inside and outside the ear
  • Windows-based certified individual (F-MIRE) Sonolab software to give field attenuation in minutes

Your business gains:

  • Fully objective testing
  • Logged PAR per individual’s hearing protector
  • Direct compatibility with REAT (Real Ear Attenuation at Threshold) – the ‘gold’ standard
  • Customised protection to optimised noise levels
  • International standards with multi-lingual compatibility

Different levels of attenuation are available for noisy environments where communication is required

You can choose the most appropriate attenuation level when you use Sonolab Instant Fit Custom Moulded Earplugs. This means that where it’s necessary, you have easy communication without the need to remove the ear plugs.

The variations in attenuation level are attained through the use of specific filters, made of mesh fabric contained inside a metallic stainless steel cylinder. These acoustic dampers allow you to reach the optimal protection outcome which is between 75-80dB (noise reaching eardrum).

Three models of filters are available: Black ‘Full Block’ SNR 27; yellow SNR 24 and Red SNR 21.

Test frequencies (Hz)631252505001000200040008000SNRHML
Black (Full Block)Mf (dB)29.530.527.126.125.736.334.843.127292323
sf (dB)
APVf (dB)24.323.922.620.922.231.331.538.7
YellowMf (dB)15.41819.519.621.72930.734.824252017
sf (dB)
APVf (dB)10.413.916.31720.12527.228.5
RedMf (dB)10.712.815.515.719.327.529.634.221231714
sf (dB)
APVf (dB)710.513.813.417.122.425.228.7


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Note: North American ANSI S12.6-1997(B), ANSI S3.19-1974 and Australia AS/NZ S1270:2001 use different calculation methods. To find out more regarding technical specifications, certifications and attenuation data corresponding to these and/or any other standard, please contact us.

CE Mark test results

To gain accreditation for the CE Mark we had to go through the testing of 16 individuals where the attenuation rating was recorded over 8 frequency ranges. As you will see, the average overall PAR rating exceeds the 30dB we publicise.

Freq (Hz)631252505001000200040008000Individual Par
Subject 1631,0235,6732,1235,3731,1344,8536,9843,7236,36
Subject 1529,4430,0023,1523,8723,0935,5532,1546,7730,50
Subject 1427,5827,4520,8425,3020,4027,8532,0839,8827,67
Subject 1336,2534,6528,0533,2027,6843,6035,7237,6034,6
Subject 1228,3328,4027,5230,3329,1337,8041,7337,3532,57
Subject 1126,8224,2225,4525,0032,9740,9836,7746,7032,36
Subject 1018,1219,8520,0220,4024,5532,4035,4047,7227,31
Subject 928,5533,6826,0821,9724,9228,6035,5743,9730,42
Subject 835,6840,8329,5522,5821,5337,7029,3041,1232,29
Subject 726,2524,4829,8722,0025,1240,6735,6244,9531,12
Subject 623,2822,5821,9818,1222,6230,5029,4034,6225,39
Subject 526,5525,5029,7330,0525,3838,7735,3043,4031,84
Subject 428,5031,9330,7031,5026,7832,4532,5347,9832,80
Subject 334,7836,1329,9729,2024,3035,1638,7748,5534,61
Subject 238,2840,1835,3529,1728,7036,4033,4545,9435,93
Subject 131,7827,0822,5520,0523,1836,7635,5938,5829,45
Ave. Freq. Attenuation29,530,227,126,125,736,334,843,131,6
Std. Dev5,16,34,45,23,55,03,24,4


Validate the hearing protection that you provide to each employee

Noise-induced hearing loss has become the number one industrial injury claim in the UK.

Until now it’s been almost impossible for an employer to refute such a claim.

This is because most testing is subjective. It relies on the person being tested wearing a pair of earphones over their protection device, and pressing a button when they can no longer hear the noise.  The subjective decision of when to press lies with the claimant, and the employer is powerless.

Now, there is a solution which provides an objective way of testing certain hearing protection, placing strong evidence in the employer’s hands.

How does the objective test work?

The test provides a personal attenuation rating (PAR) not only for each employee, but also for each of his or her ears. This is important because each individual experiences a slightly different level of attenuation from other people, and each ear is usually different too.

The equipment is designed to test the attenuation provided by SonoLab Instant Fit Custom Moulded Earplugs, and comprises:

Windows-based F-MIRE (Field Microphone in Real Ear) SonoLab software

  • This yields values comparable to the ‘gold standard’ REAT testing (real-ear attenuation at threshold)

Dedicated calibrated

  • Dual-microphone
  • Speaker and Computer if required

The dual-microphone probe fits deep inside the uniquely-designed hearing protection device (HPD). A moderate white noise is emitted from the speakers, at approximately 85 decibels – exactly the same level for every person being tested. The microphone simultaneously measures the sound pressure beneath the device (see ‘A’ on illustration to the right) and at the outside surface of the hearing protection device (see ‘B’).

‘A’ is measured using the microphone probe, which is inserted into a sound bore that traverses the length of the HPD. Sound pressure level is compared inside and outside the HPD. The difference in decibels measures the noise reduction provided by the HPD.

The SonoLab test is scientifically accurate

During the process, the software applies compensation factors/tolerances derived from rigorous laboratory testing, so the results are accurate.

Automatic documentation per employee

Each employee test is recorded on the SonoLab software, giving Reportable Personal Attenuation Rating.

Stockist Info

Summary of features and benefits

  • Certified individual F-MIRE (field microphone in real ear) in just a few minutes
  • Direct comparability with REAT (real ear attenuation at threshold), the ‘gold standard’ of testing
  • Reportable PAR (personal attenuation rating) for each employee, and for each ear
  • Tests customised protection to optimal noise environments
  • International standards with multi-lingual compatibility
  • 64-bit compatible

Hardware requirements

Minimum computer requirements for installing the SonoLab Noise Attenuation Testing Software are:

ProcessorIntel Pentium IV or AMD
Processor speedI GHz (2.4 GHz recommended)
RAM512 MB (1GB recommended)
Screen resolution1024 x 768
Operating system(32 x 64 bit) Windows 2000, Windows XP, Vista, Windows 7   . Must run with Administrator Privileges  
Free disk space120 MB
USB port1 USB VI.I
Internet accessDialup 56 Kbps (Cable or DSL preferred    )
Installation driveCD-ROM, DVD drive, USB   

Product use
All statements, technical information and recommendations contained in this document are based upon tests or experience that SonoLab believes to be reliable. However, many factors beyond SonoLab’s control can affect the use and performance of a SonoLab product in a particular application, including the conditions under which the product is used and the time and environmental conditions in which the product is expected to perform. Since these factors are uniquely within the user’s knowledge and control, it is essential that the user evaluate the SonoLab product to determine whether it is fit for a particular purpose and suitable for the user’s method of application.

Warranty and limited remedy
Unless stated otherwise in SonoLab’s product literature, packaging inserts or product packaging for individual products, SonoLab warrants that each SonoLab product meets the applicable specifications at the time SonoLab ships the product. Individual products may have additional or different warranties as stated on product literature, packaging inserts or product packages. SonoLab makes no other warranties, express or implied, including, but not limited to, any implied warranty of merchantability or fitness for a particular purpose or any implied warranty arising out of a course of dealing, custom or usage of trade. User is responsible for determining whether the SonoLab product is fit for a particular purpose and suitable for user’s application. If the SonoLab product is defective within the warranty period, your exclusive remedy and SonoLab’s and seller’s sole obligation will be at the SonoLab’s option, to replace the product or refund the purchase price.

Limitation of liability
Except where prohibited by law, SonoLab and seller will not be liable for any loss or damage arising from the SonoLab product, whether direct, indirect, special, incidental or consequential, regardless of the legal theory asserted, including warrant, contract, negligence or strict liability.