42 CFR § 84.199
Facepieces, hoods, and helmets; eyepieces; minimum requirements
June 11, 2020
Facepieces, hoods, and helmets shall be designed and constructed to provide adequate vision which is not distorted by the eyepieces.
Facepieces, hoods, and helmets shall be designed and constructed to provide adequate vision which is not distorted by the eyepieces.