bus 为什么没有安全带

billzhao

每年因为车祸死亡或者受伤的乘客不在少数，很多是由于汽车侧翻以后被甩出去撞上硬物。不管公交车，旅游车，长途车，还有校车，都没有安全带，为什么呢？

下面的解释比较牵强

If cars have seat belts, why aren't they generally required in school buses? Because modern school buses are already remarkably safe, and because seat belts don't work the same way in buses as they do cars, research shows.

Numerous federal and academic studies have concluded that school buses are the safest form of ground transportation of all, in fact. The National Safety Council says they're about 40 times safer than the family car.

# k+ P: x6 G6 S+ TAbout 440,000 public school buses carry 24 million children more than 4.3 billion miles a year, but only about six children die each year in bus accidents, according to annual statistics compiled the National Highway Traffic Safety Administration. About 800 children, by contrast, die every year walking, biking or being driven to school in cars or other passenger vehicles, said Ron Medford, the agency's deputy director.

That's because designers of modern school buses don't trust squirmy children to use seat belts properly. Instead, they use a passive system called compartmentalization. Bus seats aren't packed so closely together just to maximize capacity (although that's one reason); they're spaced tightly and covered with 4-inch-thick foam to form a protective bubble.
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In a crash, "the child will go against the seat, and that will absorb most of the impact," said John Hamilton, transportation director for the Jackson County, Fla., school board. "Plus, it's a safety device so that they won't be projecting through the air."

billzhao

Safety experts, including the Canada Safety Council, do not believe seat belts on school buses would improve safety. There is no scientific evidence that lives would be saved. Transport Canada has applied approximately 40 safety standards to the design and construction of school buses made in and imported into Canada. These include specialized brake systems, lighting, emergency exits, escape hatches in the roof, and high padded seatbacks that cushion the impact of a crash.
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' G+ o" K: d3 ]" E. TSchool buses are not passenger vehicles. They are built to rely on safety not on seat belts, and are designed and constructed differently from passenger cars. They are bigger, heavier, and higher so they have a body-on-frame design. Newer systems, such as an anti-lock braking system would be more beneficial.

School buses protect passengers through “compartmentalization,” a design that includes:

- X" }4 g4 a/ KSeats with high backs;
Seats filled with energy-absorbing material;
Seats placed close together to form compartments;
Strong seat anchorages.
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Research has shown that lap belts could actually increase the risk of head injuries in a head-on collision (the most common type of bus collision). By holding the child’s pelvis firmly in place, the torso would whip forward; with the head striking the back of the seat in front of them with greater force than if the whole body had hit the seat. This could result in serious head and neck injuries.

# O9 L* \# U* Y3 t. f( T0 a这一段是废话，谁家的安全带光固定屁股？
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Combination lap and shoulder belts would require stiffer seats, which could increase injury to students who are not buckled up. The driver cannot ensure that every child has their seat belt on; some buses can carry up to 70 children. Moreover, the shoulder belts can lead to abdominal injuries because of “submarining” – when children slip down, risking injuries to organs covered by the lap belts.

这一段也是废话，说司机没有办法保证学生都系上安全带。这不能说明安全带没有用。
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Beyond certain engineering problems, someone would need to ensure the seat belts are used, adjusted properly between uses by smaller children and larger children and repaired when damaged. In an emergency, seatbelts could hinder evacuation. Young children should not be placed in a situation where they are responsible for their safety.