
Tunnel dotted lines do not allow lane changes. Inside the tunnel, you should follow the vehicle in front in sequence and avoid changing lanes or overtaking. Because tunnels have fewer lanes and relatively poor visibility, you should slow down in advance before entering the tunnel, clearly observe the internal conditions, and maintain an appropriate distance from the vehicle in front at the specified speed. Precautions for driving through tunnels: Be especially careful when exiting the tunnel, as sometimes the sunlight outside can be blinding; other times, especially in long mountain tunnels, the weather might be fine before entering the tunnel, but there could be rain, snow, or thick fog at the exit, leading to accidents if unprepared. Some tunnel exits may also have curves or uphill/downhill slopes, and lack of anticipation can also cause accidents. If a vehicle breaks down or is involved in an accident inside the tunnel and cannot leave the scene immediately, turn on the hazard warning lights and place a warning sign 50 to 100 meters behind the vehicle. The driver and passengers should quickly exit the vehicle and leave the tunnel along the side to the roadside guardrail, then call the police immediately to avoid secondary accidents inside the tunnel.

I thought about this during my last long-distance drive. In theory, you can change lanes when you see dashed lines in a tunnel, but I sincerely advise against it. Tunnels are narrow and poorly lit, and drivers behind you take time to adjust their eyes to the darkness, so their reaction is slower. Once, I was following too closely when the car ahead suddenly changed lanes, and I had to slam on the brakes—water bottles in the trunk spilled everywhere. Think about it: the risk of rear-end collisions in tunnels is at least 30% higher than on regular roads. Plus, many tunnels have full surveillance, and crossing the line will get you a ticket—more effective than coffee at waking you up. If you're in a hurry, just wait until you're out of the tunnel to change lanes. Safety first.

During the driving test, the instructor repeatedly emphasized: the dotted line in the tunnel is just for show! Although the traffic laws don't explicitly prohibit it, it's extremely dangerous in practice. The tunnel lighting strips interfere with judgment, rearview mirror visibility is blurry, and changing lanes can easily cause following vehicles to misjudge distances. A friend of mine scraped a bumper while changing lanes in a tunnel, was ruled fully at fault by traffic police, and the insurance didn't cover mental distress compensation. Poor ventilation and thick exhaust fumes can easily make drivers dizzy. Nowadays, newly built smart tunnels are equipped with millimeter-wave radar that alerts when crossing lines. Just follow the car in front steadily and wait until the exit to make any moves.

Personally tested, the 10-second dark adaptation period is deadly. That time entering the tunnel, just as my eyes adjusted to the darkness, the car ahead suddenly crossed the dashed line to change lanes. I slammed the brakes and almost hit the wall. Experimental data shows: the safe distance required for lane changes in tunnels is 5-8 meters longer than during daytime. Poor ventilation and low visibility, with exhaust fumes fogging up the windshield. Nowadays, navigation systems come with real-time tunnel alerts, so I always merge into the correct lane 1 kilometer in advance. Speaking of which, Hangzhou's Zizhi Tunnel installed a lane-change monitoring system last year, catching over 200 violations daily on average.

When modifying my car, I consulted a traffic police buddy who said verbatim: 'The dashed lines are reserved for emergency vehicles!' For regular cars changing lanes in tunnels, the scratch rate skyrockets by 40%. Ventilation systems have many dead zones, and amplified tire noise makes it hard to hear horns from adjacent lanes. Last time, my dashcam caught a lane change in the tunnel causing a three-car pileup—airbags deployed. It's recommended to activate lane-keeping assist; the steering wheel will automatically resist drift. During claims, insurers specifically review tunnel footage—illegal lane changes directly impact compensation amounts.


