Which action is prohibited while driving a commercial motor vehicle (CMV)?

Holding a cell phone to make a call while driving a commercial motor vehicle (CMV) is prohibited because it significantly increases the risk of distraction. The Federal Motor Carrier Safety Administration (FMCSA) has stringent regulations in place to ensure the safety of CMV operators and the public, recognizing that any hand-held phone use can divert attention away from the road. This distraction can impair a driver's ability to react to road conditions, other vehicles, and pedestrians, leading to a greater likelihood of accidents.

In contrast, using hands-free devices may be permitted under certain guidelines, as they allow the driver to keep both hands on the wheel while still managing communication. Listening to the radio and eating while driving, while not recommended for safety reasons, do not fall under the same prohibited activities as hand-held phone use, which directly contravenes regulatory standards aimed at minimizing driver distraction.