Ohio Rev. Code Ann. § 4104.04
(A) Sections 4104.01 to 4104.20 and section 4104.99 of the Revised Code do not apply to the following boilers and pressure vessels:
(B) The following boilers and pressure vessels are exempt from the requirements of sections 4104.10, 4104.101, 4104.11, 4104.12, and 4104.13 of the Revised Code, but shall be equipped with such appliances, to insure safety of operation, as are prescribed by the board: