§18.66. Tests of windows and lenses. — Inbound Citations

(a) MSHA may waive testing of materials for windows or lenses except headlight lenses. When tested, material for windows or lenses shall meet the test requirements prescribed in § 18.66 and shall be sealed in place or provided with flange joints in accordance with § 18.31.

(c) Lenses for headlights shall be glass or other suitable material with physical characteristics equivalent to 1/2-inch thick tempered glass, such as “Pyrex.” Lenses shall meet the requirements of the tests prescribed in § 18.66.