Choosing the proper hearing protector depends mainly on its NRR or Noise Reduction Rating. It is an index which measures the performance of a hearing protection and how it reduces the noise. When selecting hearing protectors , it is necessary to select products with the appropriate NRR depending on the work environment. This article will help you understand NRR values and how to select the suitable hearing protection for your work.
What is a hearing protector?
Hearing protectors are an essential product to protect workers from noisy environments. When working in a noisy environment, not only does the noise interfere with the worker's concentration, but can also damage the worker’s tension if exposed for a long period of time. These problems can be prevented by wearing appropriate hearing protectors.
There are various types of hearing protectors , such as earplugs and earmuffs, and each has various ranks of products depending on performance and size.
These are small earpieces made mainly of urethane or silicone that are inserted into the ear canal to physically block noise to some extent. There are variations of hearing protectors , including reusable and disposable, special waxed cotton and fiberglass cotton.
A headphone-type shape that is attached to the head and covers the entire ear to block out noise.
NRR (Noise Reduction Rating), also known as Noise Attenuation Index, is a numerical value (unit: dB, decibel) that indicates the sound insulation performance of hearing protectors as defined by the United States Environmental Protection Agency. The higher the value, the higher the sound insulation performance.
What is an appropriate NRR?
It is best to determine the appropriate performance or NRR needed when using hearing protectors. If you are working with over-specified hearing protectors, it may block out some signal sounds or human voices that you need to hear, which may lead to danger. Therefore, it is important to select products with adequate performance.
The NRR value of the product minus the noise level generated at the site should be between 80dB and 84.9dB. In other words, if the noise level at the site is 115dB and you use an earplug or earmuff with an NRR of 31dB, the following would apply
115dB-31dB = 84dB
How to choose the appropriate hearing protector?
There is a great variety of hearing protectors on the market, even a single pair of earplugs. Below are the guidelines to help you choose the right hearing protectors.
Check the noise range
The difference between the noise level at the site and the NRR value of the hearing protector is important when selecting a product t.
However, some products may have NRR values listed by sound range. For example, if a product has a low NRR value in the lower frequency range and a high NRR value in the higher frequency range, it can be determined that it is better at blocking out high noise than low noise. If you want to block out noise with greater pinpoint accuracy, it is best to include such products into considerations.
Check the fit
The shape of the ear canal varies from person to person. When using earplug-type protectors, the most important factor to consider is whether the product fits the ear properly. Even if a product with an appropriate NRR value is selected, if it does not fit well, the expected performance will not be achieved. If there is no product that fits, it is also best to consider earmuff-type products.
Hearing protectors have important use in the workplace. It protects workers from noise and provides a comfortable work environment.
Always remember to select the appropriate hearing protectors based on two key points: NRR value and proper fit.