Assessment methods for personal Active Noise Reduction validated in an international round robin [Méthodes d’évaluation des protecteurs auditifs à atténuation active du bruit]

Hearing protection with standard passive earmuffs is for many military applications insufficient. Low frequency noises (diesel engines, helicopter rotor) require increased attenuation. Active Noise Reduction (ANR) is specifically suited for reduction at low frequencies. Assessment of ANR for military applications is an important topic as the adverse military environment may cause unexpected reduced performance (e.g. very low rotor-blade noise may overload a for civil applications designed system). This study contains assessment methods for ANR in military applications from five laboratories.