Ohio Rev. Code § 1567.36: Fire extinguishers.

At each permanent underground oil storage station there shall be two portable fire extinguishers and two hundred forty pounds of rock dust. One portable fire extinguisher shall be provided at each working section where twenty-five gallons or more of oil are stored in addition to extinguishers required under other sections of this chapter.

No operator of a mine shall refuse or neglect to comply with this section.