What is the speed limit and distance requirement when visibility is below 100 meters?

[Marvin]

When visibility is below 100 meters, the speed limit is 40 kilometers per hour, and the distance between vehicles should be more than 50 meters. Additionally, fog lights, low beam headlights, outline marker lights, front and rear position lights, and hazard warning flashers should be turned on. Maintain a distance of more than 50 meters from the vehicle ahead in the same lane. When driving on highways under low visibility conditions such as fog, rain, snow, dust, or hail, highway management authorities should display speed limits and distance-keeping reminders via electronic signs. The distance a vehicle travels per unit of time is referred to as speed, commonly measured in kilometers per hour or meters per second. Vehicle speed is one of the three key parameters in traffic flow theory and holds significant importance in traffic flow studies.

[MacAlaina]

When driving in fog with visibility below 100 meters, I always reduce my speed to under 50 kilometers per hour. The reason is simple: if there's a sudden obstacle or accident, this low speed gives me enough time to react and avoid a collision. The safe distance should be kept at least 100 meters or more, because I once followed too closely on the highway and almost rear-ended another car; now I deliberately increase the spacing to ensure I can stop safely. Headlights and rear fog lights must be turned on, otherwise others can't see you clearly. I always remind my friends not to rush in such weather—slow is fast, and you'll regret it if an accident happens. Checking tire pressure and the braking system is also crucial; don't let small issues ruin your safety. Life is more precious than anything else—it's better to arrive late than not at all.

[HadleyLee]

According to driving regulations, when visibility is less than 100 meters, the speed should be controlled within 50 km/h, with 45 or 40 km/h being more reasonable. For the safe distance, I follow expert advice and set it equal to the visibility value itself, which means 100 meters or more. I've read in the driving manual that this compensates for the increased braking distance. Turning on all lighting signals is essential to alert vehicles in front and behind. Regular vehicle maintenance should not overlook light group inspections to ensure proper functioning. In rainy or foggy conditions, these rules can be life-saving, and I never take chances by speeding. Staying calm, planning routes in advance to avoid sudden braking, and developing good habits greatly benefit long-term driving. Remember, traffic laws are designed to protect everyone—violating them doubles the risks, endangering both yourself and others.

[LaQuinn]

I was driving in heavy fog and only felt stable when I reduced my speed to 40km/h. I had to increase the following distance, leaving a 120-meter gap to ensure I could brake safely if something happened ahead. My headlights and rear fog lights were on the whole time—otherwise, it would have been like driving blind. Experience has taught me not to speed; slowing down is the only option. Checking that your lights are working properly is crucial, or others won’t see you. Stay focused on the road—no distractions like checking your phone. Over time, I’ve learned that gradually reducing speed a few kilometers early helps me adapt better. In short, safety comes first—don’t let low visibility become the cause of an accident. Simple principles, but easy to forget—make them a habit.

[VonJake]

From a vehicle performance perspective, when visibility drops below 100 meters, the speed should not exceed 50km/h. Keep the engine RPM low and steady, with quick brake response. Maintain a minimum following distance of 100 meters to prevent overloading the ABS system. I make sure to turn on the fog lights and rear fog lights, and keep the signal lights on to enhance visibility. Why is distance crucial? Because braking distance increases – an extra 5 meters of buffer space is needed for every 10km/h speed increment. Ensure good tire traction and conduct regular checks to prevent skidding. Driving in such weather requires patience – systematically inspect lighting and electrical components, as minor issues can trigger chain-reaction accidents. Overall, reduce speed and increase distance, prioritize safety, and don't let haste make you overlook critical details.

[McAshlyn]

An experienced driver taught me that when visibility is less than 100 meters in foggy conditions, it's safest to keep your speed under 40 km/h. Increase your following distance, aiming for 120 meters or more, using the taillights of the vehicle ahead as a reference point to maintain distance. Always turn on your headlights and rear fog lights to make yourself more visible to others. The key technique is to slow down in advance, don't wait until you're close to an accident to brake; check if your lights are working properly, preventing malfunctions is crucial. I've developed the habit of checking the rearview mirror to ensure no one is approaching too closely. Staying calm while driving is essential—losing a little time by going slower is minor compared to the potential loss of life. Safety is ten times more important than punctuality, and making this a habit will soon feel natural.