NBN EN 352-9:2020+A1:2024

This document is applicable to earplugs supplemented by a safety-related audio input. The audio signal can be transmitted by electrical input or other communication like Bluetooth . It specifies requirements on construction, design, performance, marking and user information related to the inclusion of the safety-related audio input.
Earplugs with safety-related audio input are designed to provide speech information and warning signals, while providing attenuation of external sound. They may be selected for use in a number of different environments, for example in air traffic communication, in the police forces, in the broadcasting and entertainment industries.