R 408.13353 Lenses.

Rule 3353. (1) Lenses intended for use in eye protectors are of 4 basic types, as follows: (a) Clear lenses which are impact-resisting and provide protection against flying objects. (b) Absorptive lenses of shades 1.7 through 3.0 which are impact-resisting and provide protection against flying objects and glare or which are impact-resisting and provide protection against flying objects, and narrow-band spectral transmittance of injurious radiation. (c) Protective-corrective lenses which are impact-resisting and either clear or absorptive, as specified for persons requiring visual correction. (d) Filter lenses which are impact-resisting and provide protection against flying objects and narrow-band spectral transmittance of injurious radiation. (2) Glass filter lenses intended for use in eyecup goggles shall be heat treated. (3) The height of the safety lens shall not be less than 30 millimeters.