This part of the standard specifies constructional, design and performance requirements, marking requirements and user information for ear-plugs. In particular, it specifies the sound attenuation of the ear-plugs, measured in accordance with EN 24869-1. Ergonomic aspects are addressed by taking into account, within the requirements, the interaction between the wearer, the device and where possible the working environment in which the device is likely to be used (see Annex ZA and EN 458).