GMC 2009 Sierra - Manual (Page 15)

In most states and in all Canadian provinces, the law
requires wearing safety belts. Here is why:
You never know if you will be in a crash. If you do have
a crash, you do not know if it will be a serious one.
A few crashes are mild, and some crashes can be so
serious that even buckled up, a person would not
survive. But most crashes are in between. In many of
them, people who buckle up can survive and sometimes
walk away. Without belts they could have been badly
hurt or killed.
After more than 40 years of safety belts in vehicles, the
facts are clear. In most crashes buckling up does
matter... a lot!
Why Safety Belts Work
When you ride in or on anything, you go as fast as
it goes.
Take the simplest vehicle. Suppose it is just a seat on
wheels.
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