Before passing on a two-lane road, what must a driver check first?

Before attempting to pass on a two-lane road, the foremost action for a driver is to check the rearview and side mirrors. This allows the driver to assess the surrounding traffic conditions, including the speed and proximity of vehicles behind them and to the sides. Ensuring that it is safe to change lanes or maneuver is crucial to avoid collisions and maintain safety.

Looking in the rearview and side mirrors provides awareness of any vehicles that may also be preparing to pass or change lanes, which is vital in understanding the full scope of the roadway environment. It is also important to note the positioning of other vehicles, as drivers need to have a clear path before executing a pass, reducing the risk of accidents.

While headlights, speedometers, and traffic signs are important for overall driving safety, they do not directly contribute to validating the safety of passing, making them less relevant in this particular scenario.