The adoption of dBA‐type hearing damage risk criteria and the consequent use ofA‐weighted sound levels to identify areas of auditory hazard have created a need for a measure of the dBAattenuation of ear protectors. In Study 1, the dBAattenuation values of 30 ear protectors are calculated in 619 industrial noise spectra. It is found that the same ear protector may offer 20 dB more dBAattenuation to one noise than to another but that noises of likeC‐Avalue are subjected to approximately the same dBAattenuation. Noises are therefore sorted into five classes according toC‐Avalue, and average dBAattenuation values for each class are calculated for each ear protector. This type of information makes it possible to select adequate ear protectors even though only theC‐ andA‐weighted sound levels of the noise environment are known. In Study 2, a simple procedure is developed for calculating the dBA attenuation values of any ear protector for the fiveC‐Aclasses defined in Study 1. The procedure incorporates correction factors which ensure that, for the average protector, the calculated dBAattenuation values are obtained in 90% of spectra.