Reclining the passenger seat and dozing off on a long trip is a pleasure many of us have enjoyed. But it is a dangerous pleasure. If a passenger seat back is reclined, most seat belts become much less effective if not completely useless. As the space between the occupant’s chest and the seat belt increases, the risk of death or serious injury increases substantially. A sudden stop can cause the human body to submarine under the belt. The forces of impact that should be spread across the strong pelvis slide up to the abdomen and under the ribs. When the forces are not absorbed by the pelvis but by the abdomen, serious internal injuries are the result.

Automobile manufacturers have known about this danger for years but have resisted either redesigning seat belts to make them safer or effectively warning occupants about the risks involved in reclined seats.[1]

In 1988, the National Transportation Safety Board examined 167 collisions involving occupants who wore a three point restraint system. The three-point system was very effective in restraining properly positioned occupants. The study found, however, that an occupant wearing a seat belt in a reclined seat was not centered in the belt.  As a result, the restraint system was rendered ineffective for spreading crash forces across the body. The study concluded that a lap/shoulder belt in a reclined seat may be a potentially dangerous combination in a moving vehicle because proper fit was impossible.

The NTSB issued safety recommendations to the National Highway Transportation Safety Administration recommended that manufacturers limit the angle of recline to no greater than the maximum angle that permits a seat belt to fit properly. Unfortunately, automobile manufacturers have insisted that warnings to the public in owners’ manuals are sufficient.[2]

To prevent serious injuries, another proposed solution is to make the warnings prominent in the passenger compartment.  Despite awareness of this problem for over two decades, however, few people outside of the auto industry are aware of this danger.   Obviously the warnings to date have been ineffective.[3]

A better solution to the problem is to redesign seats and belts to eliminate the problem.   For instance, GM has begun to incorporate a seat design in some of its current vehicles that mounts the seat belt within the seat itself. This design allows the shoulder harness to stay in position when the occupant reclines the seat.

Unless you own one of the new GM cars with this new seat belt design, be cautious how far you recline your seat if you take a nap beside the wheel.

[1] As often occurs, despite knowledge of a danger or safety defect, automobile manufacturers do not implement design changes to prevent the danger until a lawsuit forces them to do so.   In a recent suit in San Angelo, Texas, a court held that Hyundai’s reclining seat caused the death of a passenger.  See http://www.gosanangelo.com/news/2010/apr/28/san-angelo-federal-jury-issues-18m-judgment-car/.

[2] In the Goodner v. Hyundai case noted in the footnote above, Hyundai claimed that the reclining seat was only supposed to be used when the car was not in motion, and actually blamed the passenger for not reading the small print warning in the owner’s manual.   This case also illustrates why warnings alone are generally not effective.  See http://www.prnewswire.com/news-releases/hyundai-reclining-seat-kills-in-car-accident-injury-attorney-todd-tracy-issues-car-safety-alert-91943099.html.

[3] For instance, as far back as 1988, the Ford Mustang, Ford Thunderbird, Mercury Cougar, and Mercury Grand Marquis Owner’s Manuals included the following warning, yet very few owners have ever been aware of this precaution or the nature of the associated dangers: “Warning: To minimize the risk of a personal injury in the event of a collision or a sudden stop, both the driver’s and the passenger’s reclining seatbacks must always be in a fairly upright position while the vehicle is in motion. The protection provided by the seat and shoulder belts is significantly reduced when the seatback is not in the upright position.” See http://www.orangecountylaw.com/lawyer-attorney-1359423.html.