Hearing protector fit testing measures the amount of noise reduction, or attenuation, a Hearing Protection Device (HPD) provides while worn by a specific individual. This real-world measurement is known as a Personal Attenuation Rating or PAR. The purpose of hearing protector fit testing is to verify that the attenuation is adequate for the individual and to help validate HPD’s that can be used successfully in their work environments. Safety professionals worldwide recognise that conducting hearing protection fit testing is best practice, one that considerably improves the outcomes of hearing conservation programmes to help better protect workers.
There are various types of fit test systems, but in general terms, the worker chooses the hearing protector they typically use, it is then tested on them to learn how much noise reduction there is. Some systems are subjective, requiring the worker to respond to a sound. Others are objective and don't depend on the worker's hearing or ability to take a test. The point is, the attenuation or protection provided is determined on the individual worker and the way they typically use the tested hearing protector. Ideally, for optimal performance, a fit test system should satisfy the following criteria:
The interval for a physical calibration should be defined, it is recommended that it not exceed two years. A Field Attenuation Estimation System (FAES), a quantitative method for individual fit testing of hearing protection devices, should have a procedure to check the sensitivity of the microphones on a daily basis.
Maximum allowable ambient sound
The maximum allowable ambient noise level limit must be specified in the user instructions.
Maximum sound exposure caused by the test signal
The FAES test signals must not exceed an exposure of 80 dB LA8hn or level of 105 dB LAmax over the course of a work shift to the unprotected bystander. If the FAES output exceeds these limits, the manufacturer must specify suitable protective methods.
Bias or non-linearity of fit test results
Bias or non-linearity is evaluated by comparing the FAES measurement results to the real-ear attenuation at threshold reference test values. The manufacturer must assess and minimise any bias to decrease the measurement uncertainty.
Range of valid attenuation measurements
The full range of measurable attenuation values must be assessed and reported. For psychophysical FAESs, this applies to people whose hearing thresholds show up to 25 dB of hearing loss.
The components of uncertainty must be evaluated, documented and made available to the user.
In addition to evaluating the performance criteria set out above, there are more detailed questions you should consider asking about a fit test system before out-laying any funds. Below is a list of questions compiled to assist you in making the right decision. If each of the questions can’t be answered with a confident “Yes,” it may be worth considering other options before investing.
The 3M™ E-A-Rfit™ Dual-Ear Validation System is specifically designed to meet each of the requirements discussed above to help ensure an optimal and accurate user experience. Here are your top 10 questions answered:
|1||Does a fit test system benefit a hearing conservation programme?||Yes||The 3M™ E-A-Rfit™ System can benefit your hearing conservation programme in many ways. Some benefits include identification of at-risk employees, allocation of suitable validated HPD's, provides a one-on-one training and motivation setting as well as valuable test records. Hearing protector fit testing is a way to measure the amount of noise reduction, or attenuation, a hearing protector provides while it is being worn by a specific individual. This real-world measurement is referred to as a “Personal Attenuation Rating” or PAR. So, like respirators, the worker can better understand the level of protection they can achieve with a properly fitted hearing protector.|
|2||Does the system test both ears at once?||Yes||The 3M™ E-A-Rfit™ System 5.0 tests both ears at the same time.|
|3||Can the system test both earmuffs and earplugs?||Yes||3M™ E-A-Rfit™ System can test most of the 3M earplugs, earmuffs and PELTOR™ Communication products.|
|4||Does the system measure seven frequencies used to predict protection?||Yes||3M™ E-A-Rfit™ System objectively measures attenuation at seven frequencies, from 125 Hz to 8000 Hz, all at the same time to better estimate the full spectrum of a worker's overall protection.|
|5||Can fit tests be done if there is background noise in the test area?||Yes||Fit tests using 3M™ E-A-Rfit™ System can be done virtually anywhere, even if it is noisy in the background (up to 85 dBA). It does not require a quiet or sound-treated room for testing.|
|6||Is the system objective?||Yes||With objective systems, the worker does not have to respond or make a judgement about the test signals, simplifying the process and reducing prep time. This approach also allows the 3M™ E-A-Rfit™ System to test seven frequencies simultaneously, in under five seconds.|
|7||Is the fit test fast?||Yes||3M™ E-A-Rfit™ System tests both ears at the same time in under five seconds, allowing quick identification of workers needing intervention, documentation of results, and supports efficiencies in your hearing conservation programme.|
|8||Can the system be used to test workers with hearing loss?||Yes||Because 3M™ E-A-Rfit™ System uses an objective measurement technology it can be used on all workers, regardless of their hearing ability. Even workers who have hearing loss can be tested.|
|9||Does the system meet the requirements for calibration?||Yes||3M™ E-A-Rfit™ System meets the requirements and must be calibrated every two years, and daily verification checks must be done on the microphones.|
|10||Does the system display the uncertainty of the PAR value?||Yes||3M™ E-A-Rfit™ System has always taken a conservative approach by displaying the PAR minus the uncertainty value as the overall PAR result. The uncertainty value is shown in the software, on the Detail View tab, for each PAR measurement.|
It’s not an easy task to provide accurate protection levels for every worker, each of whom has different ears and performs a different job, as a consequence requiring individual levels of hearing protection. 3M™ E-A-Rfit™ Dual-Ear Validation System plays a vital role in the hearing conservation framework by finding your employees’ attenuation rating. This rating ensures they are getting the best hearing protection to shield noise hazards in their work environment and prevent noise-induced hearing loss.