Historical
ISO 4851:1979
Personal eye-protectors - Ultra-violet filters - Utilisation and transmittance requirements
Gives the numbering of and transmittance requirements for filters. It defines guidance and their selection and use. Optical test methods form the subject of ISO 4854. Non-optical test methods form the subject of ISO 4855. The symbol for filters includes a code number and the shade number corresponding to the filter. The determination of transmittance is described in clause 5 of ISO 4854.
International Organization for Standardization [iso]