MSHA - Code of Federal Regulations - 30 CFR 20.6
30 CFR § 20.6
(a) The lamps shall be durable in construction, practical in
operation, and suitable for the service for which they are designed and
(b) The intensity of light, distribution of light, and battery
capacity shall be adequate for the use for which the lamp is intended.
(c) Battery terminals and leads therefrom, as well as the battery gas
vents, shall be designed to minimize corrosion of the electrical
(d) Bulbs and other replacement parts of the lamps shall be
adequately marked as a means of identification.