SNR stands for Single Number Rating, which is a method used to indicate the level of noise reduction provided by hearing protectors. The SNR is a single value that represents the average amount of noise reduction that the hearing protectors provide across a range of different frequencies. The SNR value is expressed in decibels (dB), and the higher the SNR value, the greater the amount of noise reduction provided by the hearing protectors. For example, if a pair of hearing protectors have an SNR of 30 dB, they would reduce the overall noise level by an average of 30 dB.