29 CFR § 1926.441 - Batteries and battery charging.
(a) General requirements.
(1) Batteries of the unsealed type shall be located in enclosures with outside vents or in well ventilated rooms and shall be arranged so as to prevent the escape of fumes, gases, or electrolyte spray into other areas.
(2) Ventilation shall be provided to ensure diffusion of the gases from the battery and to prevent the accumulation of an explosive mixture.
(3) Racks and trays shall be substantial and shall be treated to make them resistant to the electrolyte.
(4) Floors shall be of acid resistant construction unless protected from acid accumulations.
(5) Face shields, aprons, and rubber gloves shall be provided for workers handling acids or batteries.
(6) Facilities for quick drenching of the eyes and body shall be provided within 25 feet (7.62 m) of battery handling areas.
(7) Facilities shall be provided for flushing and neutralizing spilled electrolyte and for fire protection.
(b) Charging.
(1) Battery charging installations shall be located in areas designated for that purpose.
(2) Charging apparatus shall be protected from damage by trucks.
(3) When batteries are being charged, the vent caps shall be kept in place to avoid electrolyte spray. Vent caps shall be maintained in functioning condition.