What is the difference between NNR and SNR?Updated 2 months ago

These values come from two different standards that measure how well hearing protection devices (like earmuffs or earplugs) reduce sound. In the US, we use the NRR (Noise Reduction Rating) for ANSI certification. In Europe, it's the SNR (Single Number Rating) for CE certification. Because the certification bodies use different calculation methods, SNR ratings are usually about 2-3 dB higher than NRR ratings for the same product. But both ratings reflect the same level of performance and functionality.