The Federal Motor Carrier Safety Administration (FMCSA) amends the physical qualifications for drivers and the instructions for the medical examination report to clarify that drivers may not use Schedule I drugs and be qualified to drive commercial motor vehicles (CMVs) under any circumstances. The rule harmonizes FMCSA’s provisions regarding pre-employment and return-to-duty test refusals with corresponding Department of Transportation (DOT)-wide provisions. Finally, the rule corrects inaccurate uses of the term “actual knowledge.”