Ohio Rev. Code § 4905.06
The public utilities commission has general supervision over all public utilities within its jurisdiction as defined in section 4905.05 of the Revised Code, and may examine such public utilities and keep informed as to their general condition, capitalization, and franchises, and as to the manner in which their properties are leased, operated, managed, and conducted with respect to the adequacy or accommodation afforded by their service, the safety and security of the public and their employees, and their compliance with all laws, orders of the commission, franchises, and charter requirements. The commission has general supervision over all other companies referred to in section 4905.05 of the Revised Code to the extent of its jurisdiction as defined in that section, and may examine such companies and keep informed as to their general condition and capitalization, and as to the manner in which their properties are leased, operated, managed, and conducted with respect to the adequacy or accommodation afforded by their service, and their compliance with all laws and orders of the commission, insofar as any of such matters may relate to the costs associated with the provision of electric utility service by public utilities in this state which are affiliated or associated with such companies. The commission, through the public utilities commissioners or inspectors or employees of the commission authorized by it, may enter in or upon, for purposes of inspection, any property, equipment, building, plant, factory, office, apparatus, machinery, device, and lines of any public utility. The power to inspect includes the power to prescribe any rule or order that the commission finds necessary for protection of the public safety. In order to assist the commission in the performance of its duties under this chapter, authorized employees of the motor carrier enforcement unit, created under section 5503.34 of the Revised Code in the division of state highway patrol, of the department of public safety may enter in or upon, for inspection purposes, any motor vehicle of any motor carrier.
In order to inspect motor vehicles owned or operated by a motor carrier engaged in the transportation of persons, authorized employees of the motor carrier enforcement unit, division of state highway patrol, of the department of public safety may enter in or upon any property of any motor carrier engaged in the intrastate transportation of persons.
R.C. § 4905.06