Ohio Rev. Code § 1567.02
In the operation of mines, mine owners, lessees, and their agents may continue to use the type of appliance and machinery owned or operated in such mines on September 2, 1941, in the manner permitted by the statutes in force on June 3, 1941, and until the mine in which such appliances or machinery are located is exhausted or abandoned; in the use of such appliances or machinery, they shall comply with the rules of the chief of the division of mineral resources management. In gaseous mines, as parts of such machinery or appliances become worn out and have to be replaced, the chief or the deputy mine inspector shall order that such replacement parts put the machinery or appliance in a condition or state, as far as practicable, to meet the requirements of the United States bureau of mines for permissible machinery or appliances; in case any piece of machinery or appliance is worn out and is not so connected with the use of other machinery and appliances as to make it necessary to replace such worn-out piece with the same type in order to continue the use of the connected appliances and machinery, the machinery or appliance purchased for such replacement shall be of a type made lawful under this chapter and Chapters 1561., 1563., and 1565. of the Revised Code, which in gaseous mines shall be of permissible or approved type. The chief, in making such rules, shall incorporate therein the statutes in force on June 3, 1941, governing the use of such appliances and machinery. If in the chief's opinion such statutes do not provide the required protection, additional rules to cover such use shall be made by the chief or by the deputy mine inspector, with the chief's approval. The deputy mine inspector and the electrical inspector shall, in their periodic inspection of the mines, report on the condition of all machinery and appliances to see that this section is being complied with.
R.C. §1567.02