Ohio Rev. Code Ann. § 4511.25
(A) Upon all roadways of sufficient width, a vehicle or trackless trolley shall be driven upon the right half of the roadway, except as follows:
(B)
(1) Upon all roadways any vehicle or trackless trolley proceeding at less than the prevailing and lawful speed of traffic at the time and place and under the conditions then existing shall be driven in the right-hand lane then available for traffic, and far enough to the right to allow passing by faster vehicles if such passing is safe and reasonable, except under any of the following circumstances: