What are earplugs?
Earplugs are designed to be placed inside the ear canal to protect the wearer from the damaging effects of excessive noise, or to block the entrance of water, wind, dirt or debris. They are made from a variety of materials, from foam to wax to rubber, are disposable or non-disposable and offer a wide range of protection levels.
How loud is too loud?
Sound levels above 85 decibels are dangerous to your hearing and can cause irreversible damage. Amplified music at about 110 decibels can damage your ears after four to 30 minutes of exposure.
The Control of Noise at Work Regulations 2005 came into force on 6th April 2006. It states that if the noise levels in the workplace exceed 80dB(A) (Lower Exposure Action value), hearing protection must be available on request.
If the noise levels exceed 85dB(A) (Upper Exposure Action Value), the provision and wearing of hearing protection is mandatory. An Exposure Limit of 87dB(A) has been introduced, this level of noise must not be exceeded even when wearing ear protection.
Which ear plugs will block the most noise?
All ear plugs have a NRR or a SNR number, when used correctly the higher the number the more noise the earplug will be block.
So what does NNR and SNR mean?
SNR (Single Number Rating) is a number rating used by countries within the European Union calculated from assumed protection values according to a method given in Annex D of BS EN ISO 4869-2:1995 “Acoustics – Hearing protectors – Part 2: Estimation of effective A-weighted sound pressure levels when hearing protectors are worn”.
Tests are conducted using frequencies which are slightly different to those used for the NRR rating.
SNR further rates protectors in terms of the particular noise environments in which they will be used: H for high frequency noise environments, M for mid frequency and L for low frequency. High, medium and low designation does not refer to noise level, rather the spectrum of the noise. For example, a protector might be designated with SNR 26, H=32, M=23, L=14. The estimated attenuation changes according to the noise spectrum of the environment in which the protector is to be worn.
The SNR rating is the result of a lengthy mathematical calculation, it gives us a single-number rating of a hearing protector’s attenuation for a specified percentage of the population. SNR is a very useful standardized method for describing a hearing protector’s attenuation in a single number. For instant if an environment has an a weighted noise measurement of 100dbA then by using an earplug with an SNR rating of 25db it will reduce the noise to 75db.
NRR (Noise Reduction Rating) is used in the United States. The NRR is an estimate of the amount of protection achievable by 98% of users in a laboratory setting when hearing protectors are properly fitted. The NRR labelling requirement is a standardised format for all hearing protection products distributed in the U.S.