ČSN EN 352-5 ed. 2

This document is applicable to active noise reduction (ANR) earmuffs. It specifies requirements on construction, design, performance, marking and user information related to the inclusion of the active noise reduction facility. Active noise reduction earmuffs are designed to provide additional attenuation of external sounds by means of a noise cancellation circuit. This additional attenuation is usually provided at low and mid frequencies. They may be selected for use in low frequency dominated high noise environments.