When is it necessary to signal before changing lanes?

Signaling before changing lanes is a crucial safety measure in driving. The requirement to signal at least 100 feet before making a lane change is designed to provide ample warning to other drivers on the road. This distance allows other vehicles to anticipate your movement and react appropriately, enhancing overall safety and reducing the risk of accidents.

The reasoning for this specific distance is that it gives sufficient time for the signaling driver to indicate their intention while also allowing other drivers to adjust their speed or position if necessary. This practice fosters smoother traffic flow and helps maintain an orderly driving environment.

While other options may suggest shorter distances or conditional signaling, the 100-foot requirement is the standard for ensuring that all drivers are made aware of a lane change well in advance, thereby increasing safety for everyone on the roadway.