Can Rear Seat Belts Be Left Unfastened?

[NovaLee]

Rear seat belts must not be left unfastened, as doing so not only seriously endangers the lives of front-seat occupants but also poses safety risks to oneself. In the event of a vehicle accident, without the protection of seat belts, rear-seat passengers may directly impact the front seatbacks, resulting in injuries to the nose, arms, neck, etc. The function of a car seat belt is to instantly tighten during a collision or emergency braking, securing the occupant firmly in the seat to prevent secondary collisions. Once the tightening force exceeds a certain limit, the force-limiting mechanism appropriately loosens the belt to maintain stable chest pressure. Thus, car seat belts serve to restrain movement and provide cushioning.

[OCayden]

Once when driving relatives to the airport, my aunt was fined 200 yuan by traffic police immediately after unfastening her rear seatbelt. Actually, Article 51 of the Road Traffic Safety Law clearly states all passengers must wear seatbelts, regardless of front or rear seats. Last year, Shenzhen penalized over 30,000 cases of rear-seat belt violations, with some cities deploying high-definition surveillance systems. A friend in automotive R&D shared that in crash tests, front-row mortality spikes 30% when rear passengers are unbelted, while rear occupants face 5x higher ejection risk. This regulation truly saves lives - last month on Shanghai-Nanjing Expressway, a rear-seated girl survived a rear-end collision with minor injuries thanks to her seatbelt.

[Makayla]

Last year, taking my kid to a safety class was a real wake-up call. Not wearing a seatbelt in the back seat is like strapping a time bomb to your child. During a sudden brake at 40km/h, a 10kg child can generate an impact force of 300kg, enough to shatter the front seats. A friend who works in accident investigation showed me photos: an unbelted rear passenger's forehead can dent the front seat's metal frame by three centimeters. The airbags hidden in the C-pillar by manufacturers can't save those who don't buckle up—the airbags are designed to deploy at angles calculated for bodies secured by seatbelts. In tests, unbelted occupants can actually have their jaws shattered by the airbag.

[SanEvan]

After 15 years of car repairs, I've found that the most damage from not buckling up in the back seat is actually done to the seat latches. During every inspection, I see buckles deformed from impact—the stress generated by sudden tugs on these metal components can even compromise titanium alloys. After-sales data from a certain German brand indicates that owners who don't buckle up in the back have a 65% chance of replacing seat latches within three years. Replacing a latch requires dismantling the entire seat, with labor costs that could buy three sets of seat belts. What's worse, post-repair welding can reduce the seat frame's rigidity, turning it into a tin can in subsequent accidents.