Ohio Rev. Code Ann. § 4907.50

When two or more railroads, or a railroad and an electric railway, erect a system of interlocking works or fixtures at the place where such railroads, or railroad and railway, cross each other at a common grade, or when a railroad erects such works or fixtures at a swing bridge or drawbridge where it crosses a stream, and such works or fixtures render it safe for engines or trains to pass over such crossing or bridge without stopping, such railroads may run engines or trains over such works or fixtures without stopping if such system of interlocking works or fixtures was approved by the public utilities commission, and a plan thereof prepared by such railroads and filed with the commission.