After the wheelchair is secured to the floor of the vehicle, the next goal is to keep the wheelchair rider in the wheelchair. Most vehicle-related deaths and injuries happen in secondary impacts such as when the occupant hits the inside of the vehicle or is ejected from it.

Only the bony parts of the body can withstand the forces exerted against the body by the occupant restraint. A 3-point occupant restraint acts like the seatbelt in a car. The pelvic portion of the best goes low and snug across the pelvis. The chest portion comes from the vehicle wall and crosses the collar bone and breast bone to anchor in at the pelvis. If the occupant restraint does not cross bony areas, significant injury to soft tissue can occur.

It is important to use all 3 parts of the restraint. All vehicles should have a means to modify the origin point of the chest strap on the vehicle wall. The adjustability of this origin point allows the torso restraint belt to fit either a tall or short person.

Just because a wheelchair has a "seatbelt" with an automotive or airline style buckle does not mean that this belt is a safety belt. Most positioning belts are NOT anchored to the frame of the wheelchair. They are simply screwed into the seat rails.

The following videos use a surrogate wheelchair (a wheelchair designed for repeated crash-testing) to demonstrate the contribution of 3-point occupant restraint.

1. The first video shows the consequences of using no securement at all. This gives a clear visual of the meaning of the phrase: "secondary impacts."
2. The second shows the consequences of using after market positioning devices such as butterfly harnesses, hook and loop belts, etc.
3. The third shows the extreme movement of the upper torso that happens when only the pelvic portion is used. It does however, prevent secondary impacts.
4. The fourth video shows the extreme movement that happens when only the shoulder/chest portion is used. This movement, called "submarining," can lead to significant injury to the internal organs or obstruction of the airway.
5. The final video shows the protection offered by a properly positioned, 3-point occupant restraint.

Using only the shoulder/chest portion of the occupant restraint*
*This allows the motion called "submarining" which has the potential to cause life-threatening injuries to the internal organs, neck and airway.