In what conditions is it necessary to increase following distances?

Increasing following distances is essential in inclement weather or reduced visibility conditions because these factors significantly affect a driver's ability to react and stop safely. During such situations, road surfaces can be slick from rain, snow, or ice, which increases the stopping distance required for a vehicle. Furthermore, reduced visibility makes it harder to assess the behavior of other drivers and obstacles on the road, thereby necessitating additional space to account for unexpected changes in traffic flow or conditions.

In contrast, under dry and clear conditions, vehicles can usually stop more quickly, making shorter following distances safer. Light traffic may also create a perception of safety that could encourage closer following, but it does not account for potential hazards that can arise unexpectedly, such as sudden stops or other unforeseen issues. While SUVs may have different handling characteristics compared to smaller vehicles, the need for increased following distances primarily depends on external weather and visibility factors rather than the type of vehicle being driven.