This part of the standard specifies constructional, design and performance requirements, marking requirements and user information for ear-plugs. In particular, it calls for the sound attenuation of the ear-plugs, measured in accordance with EN 24869-1, to be declared and to be not less than a specified minimum. The requirements of this standard are intended to take account of the ergonomic interaction between the wearer, the device and where possible the working environment in which the device is likely to be used (see Annex ZA, of this standard and EN 458).