30 CFR § 19.8
Protection against bodily hazard.
This hazard is chiefly due to the possible burning of the wearer by
electrolyte spilled from the battery. MSHA therefore requires that:
(a) Spilling of electrolyte. The lamp shall be so designed
and constructed that, when properly filled, the battery will neither leak nor
spill electrolyte under actual service conditions. Lamps passing a laboratory
spilling test will be considered satisfactory in this respect, contingent
upon satisfactory performance in service.
(b) Corrosion of battery container. The material of which the
container is made shall resist corrosion under conditions of use.