When is it not safe to pass another vehicle?

Passing another vehicle is not safe if you cannot complete the pass before entering a no-passing zone. No-passing zones are designated areas in which overtaking another vehicle is prohibited due to safety concerns, such as curves, intersections, or other visibility restrictions. Attempting to pass in these areas increases the risk of collisions since other drivers may not expect someone to attempt overtaking there. Following the rules of the road, including respect for no-passing zones, is essential for maintaining safety for all road users and helps prevent dangerous situations.

In contrast, while other scenarios like being in heavy traffic or on a downhill slope may present challenges, they do not universally rule out the safety of passing, as conditions can vary. Similarly, being in a hurry is not a valid reason to compromise safety regulations, but it is not a direct factor preventing the act of passing itself if done legally and safely. The key factor here is the legal restriction of no-passing zones, which prioritizes safety and clear visibility on the roadway.