What is the reason for using low beams within 150 meters when meeting vehicles at night?

[Minnie]

The reason for using low beams within 150 meters when meeting vehicles at night: Using high beams during nighttime encounters can easily create a blind spot of about 10 meters for the opposing driver. This obstructed vision typically lasts for four to five seconds, and these few seconds could very likely lead to a car accident. In winter, when icy and snowy roads are slippery, using high beams during encounters makes accidents even more likely. In cases of heavy fog, snowfall, or heavy rain where visibility is poor, low beams must be used even during the day. Common types of car headlights include halogen, xenon, and LED headlights. As the eyes of a car, headlights are not only related to the external image of a car owner but also closely linked to safe driving at night or under bad weather conditions.

[SanMax]

After driving at night for so many years, I deeply understand the core reason for using low beams within 150 meters when meeting another vehicle is to avoid dazzling the oncoming driver with high beams, which can cause temporary blindness. At this 150-meter distance, the high beam light is already highly concentrated, and shining directly can make it difficult for the other driver to see the road, especially at high speeds, which is extremely dangerous. The regulation sets 150 meters based on scientific tests that balance human eye adaptation time and braking distance. Here’s a personal experience: once, I forgot to switch my lights, and the oncoming driver nearly lost control and hit the guardrail before I completely broke this bad habit. Now, I slow down in advance, stay alert, and have developed the habit of automatically switching my lights, which is crucial for creating a safe driving environment and can prevent many tragedies.

[EverlyDella]

As someone who frequently studies traffic regulations, I believe that using low beams within 150 meters is primarily about complying with legal requirements and preventing accidents. The law mandates switching lights when meeting another vehicle because at 150 meters, high beams already provide sufficient visibility of road conditions, and continuing to use them is unnecessary. If strong light directly hits the other driver's pupils, it can cause temporary blindness, increasing the risk of collision. Data shows that many nighttime accidents stem from this issue, such as rear-end collisions on highways due to blurred vision. I recommend everyone practice and develop this habit in advance—it not only avoids fines but also maintains road harmony. Civilized driving starts with small details.

[LuciaDella]

From a technical perspective, I understand that headlight design is divided into low beam and high beam. The low beam projects downward to avoid direct glare, ensuring safety. If high beams are continuously used within 150 meters during oncoming traffic, the focused light can hit the other driver's eyes, causing pupil contraction and impairing vision. The human eye requires about 1 second to recover, during which high-speed driving can easily lead to accidents. Modern cars introduce automatic switching systems to optimize safety, but manual control requires sustained attention. Adhering to this principle can make nighttime driving smoother and reduce unnecessary risks.

[SanSara]

In daily driving, I often remind myself to switch to low beams within 150 meters, otherwise the oncoming driver may be dazzled by high beams and have difficulty seeing the road, which could easily lead to accidents. This distance is just the right safety buffer zone. I remember one time when an oncoming driver's strong lights almost caused me to hit a roadside tree - since then I've developed the good habit of slowing down and switching lights when meeting vehicles. Such simple actions can ensure safety for both parties and reflect driving etiquette. Novice drivers need more practice to avoid panic during night driving, working together to create smooth journeys.