The document specifies the scale numbers and transmittance requirements for filters against infra-red radiation. The others applicable requirements for these types of filters and the frames/mountings to which they are intended to be fitted are given in EN 166. Guidance on the selection and use of these filters is given in annex B.
DIN EN 171:2002 history
2002DIN EN 171:2002-08 Personal eye protection - Infrared filters - Transmittance requirements and recommended use; German version EN 171:2002
2002DIN EN 171:2002 Personal eye protection - Infrared filters - Transmittance requirements and recommended use; German version EN 171:2002