1.   As the bag inflates, the book will be pushed off and slide away.

2.   Both the government and automakers want to reduce the speed at which hour bags inflate.

3.   If the person is belted or seated far back from the steering wheel or dashboard, the bag will inflate quickly to cover the distance fast.

4.   If the driver or passenger is closer, the bag will inflate more slowly to avoid punching the person too hard.

5.   Once a bag inflates, it has to be replaced with a new unit.

6.   Smart bags will inflate only if the nature of the crash and the size of the passenger indicates it is the better course.

7.   The bag does not inflate until the narrow neck portion is extended.

8.   This means the bag inflates according to the severity of the collision.

9.   Federal authorities say their testing shows side air bags could kill or seriously injure young children, especially those sleeping or leaning against a door when the bag inflates.

10.   The bags would then inflate at speeds that would do no harm.