Ohio Rev. Code Ann. § 3753.01
As used in this chapter:
(K) "Stationary source" means any buildings, structures, equipment, installations, or substance-emitting stationary activities that belong to the same industrial group as described in the standard industrial classification manual, 1987, that are located on one or more contiguous properties under the control of the same person or persons, and from which an accidental release may occur. Properties shall not be considered contiguous solely because of a railroad or pipeline right-of-way.