What is the safe following distance at 100 km/h?
3 Answers
When the speed exceeds 100 km/h, a distance of more than 100 meters should be maintained from the vehicle ahead in the same lane. When visibility is less than 200 meters: Turn on fog lights, low beam lights, position lights, and front and rear position lights. The speed should not exceed 60 km/h, and a distance of more than 100 meters should be maintained from the vehicle ahead in the same lane. When visibility is less than 100 meters: Turn on fog lights, low beam lights, position lights, front and rear position lights, and hazard warning flashers. The speed should not exceed 40 km/h, and a distance of more than 50 meters should be maintained from the vehicle ahead in the same lane. When visibility is less than 50 meters: Turn on fog lights, low beam lights, position lights, front and rear position lights, and hazard warning flashers. The speed should not exceed 20 km/h, and you should exit the highway as soon as possible from the nearest exit.
I believe that at a speed of 100 kilometers per hour, the safe following distance should be maintained at least between 50 to 80 meters, based on the common two or three-second rule. Simply put, when the car in front passes a fixed point, such as a roadside milestone or streetlight, I start counting seconds and should reach the same point at least two seconds later. In terms of distance, 100 kilometers per hour is approximately 27.8 meters per second, so two seconds is about 56 meters, and three seconds is about 84 meters. This distance provides sufficient reaction time—for example, if the car in front suddenly brakes hard, I can calmly apply the brakes to avoid a rear-end collision. In bad weather, such as rain or fog, I increase the distance to over 80 meters, since braking efficiency is lower on slippery roads. Developing this habit isn't easy, but through repeated practice using roadside markers to time the gap, it gradually becomes second nature. Also, don't forget to check your tire condition—severe wear increases braking distance, and regular maintenance can reduce risks. Remember, this isn't a rigid rule; adjust flexibly based on real-time road conditions.
I've been driving for many years and often travel on highways. At a speed of 100 km/h, I usually maintain a distance of at least 50 meters from the car in front. I measure this by simple timing: I pick a reference point, and as soon as the car ahead passes it, I silently count the seconds, ensuring it takes me more than two seconds to reach that point, which roughly translates to over 50 meters. In rainy conditions or at night, I double that to about three seconds. I remember one time when the car in front suddenly braked hard, and it was this distance that helped me avoid an accident. Personally, I believe it's better not to rely solely on the car's navigation estimates but to use your eyes and intuition more, like watching road markings. The faster the speed, the greater the danger—100 km/h means you're covering 28 meters every second, and the consequences of a rear-end collision can be severe. Additionally, maintaining a reasonable distance has extra benefits, such as reducing air resistance and saving fuel. I recommend beginners start by practicing on smaller roads to build a sense of safety. In short, experience has taught me that this habit is a lifesaver.
