It is a legal requirement in Europe for manufacturers of PPE to ensure their products comply fully with regulation, conforming to essential health and safety requirements, before being able to apply the CE mark.
Due to the complexity of equipment and level of expertise required to perform product tests, the work must be carried out by specialist testing laboratories approved to national standards.
Test results, along with other technical documentation, is then assessed by an accredited Notified Body before an EC test certificate is issued to the manufacturer.
Results of testing to EN352 are used to provide attenuation data for the end user so they can assess suitability of PPE for the intended use. Attenuation data, along with details of where the product was tested and approved and instructions for use, must be provided with the PPE. Attenuation data must be expressed in the HML and SNR formats. HML provides the assumed attenuations in the individual High, Medium and Low frequency ranges. SNR is the Single Number Rating giving an overall assumed attenuation rating for the complete frequency range.