Okla. Stat. tit. 45, § 523

In mines where mining machines are used, each machine shall be equipped and provided with a sufficient shield for the protection of those employed in or about said machines or in the use and operation thereof, and said shield shall be kept in use constantly while said machine is being operated. All electric pumps inside of the mine shall receive careful attention. While in use at a permanent pumping station, such pumps shall be placed in a fireproof shed, constructed of masonry walls.