Third-Row Seat Safety
Three-point, pre-tensioning seat belts-In the past, most third-row seating positions were equipped with lap-only seat belts. Today, three-point seat belts (a lap belt with a shoulder harness) are commonplace, and they are much safer for occupants than lap-only restraints. Taking seat belt technology one step further, a few manufacturers now offer pre-tensioning seat belts in the third row. Pre-tensioning technology allows the belt to mechanically reduce slack at the time of impact, reducing the amount of movement by the belted passenger.
Tall head restraints-In a rear impact collision, when a vehicle is hit from behind, a passenger's head can be thrown violently backward. Restraining head movement is imperative to reducing whiplash or even more serious neck and head injuries. To effectively reduce or prevent injuries, headrests must be as high as the top of the passenger's head. Look for a head restraint design that doesn't need to be collapsed into the seat before the seatback is folded. This forces third-row occupants to keep the headrest in the most effective position.
Full curtain air bags-Air bags designed to deploy from the headliner down into the passenger compartment are called curtain air bags. Curtain air bags should cover the entire length of the occupied passenger compartment, offering complete protection for all three rows of occupants.
Seat design for adults-Most third-row seating positions have the passengers facing forward for ease of access to the second-row exit from the vehicle. In some instances, passengers may face rearward, or even sit sideways. Seating position isn't as important as the third-row seat being large and strong enough to safely accommodate an adult (check shoulder belt and head restraint position). If the seat is designed with an adult in mind, it will be that much stronger for a child.
Fuel tank forward-The safest location for a fuel tank is in front of, or cradling, the rear axle. This keeps the fuel tank protected from rear and side impacts that could potentially rupture the tank and cause a fuel-related fire. Newer, high-density polyethylene (plastic) fuel tanks are able to deform and remain intact after a collision, making them safer and less susceptible to damage than a metal fuel tank.
Crush zone-Vehicles are designed with front and rear crush zones to absorb the impact energy of the crash and reduce loads on passengers. In traditional sedans, the front crush zone is the engine compartment, while the rear crush zone is the luggage compartment or trunk. SUVs with third-row seating must compromise crush zone space for additional space for passengers. SUVs and crossovers should have additional bracing or structural reinforcement in the tailgate area to protect passengers in the rear and third-row seating positions.
Spare tire placement-An increasing number of new vehicles are being equipped with run-flat tires and have no spare tire. However, if the vehicle is equipped with a spare tire, it should be designed as an integral part of the crash absorption structure, adding additional passenger protection to rear seat occupants. Whether placed inside the trunk or underneath the rear of the vehicle, the tire should be firmly attached and secured to limit its movement in the event of a collision.