Yes. Put a radon test inside the inspection period. In Ohio, anyone paid to test must hold an ODH radon tester or mitigation specialist license, and a sale test must run at least 48 hours with side-by-side devices or a continuous monitor.
More detail
Start with the seller's disclosure. The Ohio Residential Property Disclosure Form asks, in its hazardous materials section, whether the seller knows of previous or current radon gas, with the level and any mitigation. An answer of "unknown" usually means nobody has tested. A pipe with a gauge on it means a system exists, so ask for its closeout package and the most recent result. During the test, the seller or occupant signs a noninterference agreement and a notice goes up at each entry, which is what lets the number stand if anyone questions it. If the result comes back at 4.0 or higher, Ohio's testing strategy for sales says fix the home, and the conversation turns to who pays. See radon in a Columbus home sale.