Can a medical examiner require additional tests before issuing a certification?

The correct answer is that a medical examiner can require additional tests based on the driver's medical history or examination findings. This is important in ensuring that the driver meets the necessary medical standards to safely operate a commercial vehicle. Medical examiners are responsible for assessing a driver’s physical qualifications, and if there are any indicators from the initial examination or the driver's past medical history that raise concerns, the examiner has the authority to request further tests. This might include tests for conditions that could affect driving ability, such as vision problems, cardiac issues, or other health concerns relevant to safe driving.

The other choices do not fully reflect the authority of medical examiners. Issuing a certification based solely on a single examination without considering additional factors would undermine the thoroughness required for ensuring safety on the road. Requiring further tests only at the driver’s request is not standard procedure; the responsibility lies with the examiner to ensure safety regardless of a driver's request. Additionally, limiting the requirement for further testing to drivers over a certain age does not align with the broader medical evaluation criteria that apply to all commercial drivers, regardless of age.