Home » Home & Style » Defective Products » 15-Passenger Vans May Present Rollover Risk

15-Passenger Vans May Present Rollover Risk

© Maggie Herman

A rash of recent rollovers in multi-passenger vans, commonly used by college athletic departments, churches, and hotels to carrying multiple passengers has focused national attention on whether these vehicles present a special risk of harm. Now the National Highway Traffic Safety Administration (NHTSA) has announced the findings of a recent study that may shed some light on the problem. From 1993 to 1997, NHTSA has collected reports of 71 single-vehicle collisions in 15-passenger vans, resulting in 126 fatalities.

The NHTSA study concluded that when 15-passenger vans are loaded with 10 or more occupants, the vehicles seem to have an increased rollover propensity. While the agency has previously reported that 15-passenger vans present the same risk of rollover as minivans, pickup trucks, and other vehicles of similar weights, the agency found that when fully loaded, a 15-passenger van presents a greater risk of rollover than when it is carrying fewer passengers.

The study examined accident data and rollover metrics in concluding that a 15-passenger van is three times more likely to roll over when loaded with more than 10 occupants than the same vehicle would be if loaded with less than 10 people. In addition, the agency found that when fully loaded (with 15 occupants) the risk of rollover jumps to six times what it is when lightly loaded.

What the accident data revealed: NHTSA looked at crash data from seven states over a three year period for seven vehicles—the Chevrolet Express 3500, the GMC Savana 3500 and Rally/Vandura G3500, the Dodge Ram Van/Wagon B3500 and Ram Wagon 3500, and the Ford Econoline E350 and Club Wagon E350. These vans were manufactured to carry cargo, but many have been modified to carry passengers instead. The agency excluded multiple vehicle crashes to exclude the effects of the impact on rollover. The data showed that only 12.3 percent of the single-vehicle crashes in 15-passenger vehicles resulted in rollover when the vehicle contained less than five occupants. The number jumped to 20.8 percent when the vehicle was loaded with five to nine passengers, and to 29.1 percent when it was loaded with 10 to 15 passengers. Vehicles loaded with more than 15 passengers showed a rollover rate of 70 percent.

What the metrics revealed: Currently, NHTSA measures a vehicles rollover propensity by looking at a vehicles center of gravity and track width to determine the risk that the vehicle will roll over when it runs off the road. The basic idea behind metrics is that the higher the vehicle is, the wider it needs to me to remain stable. The study revealed that loading a 15-passenger van to capacity shift the center of gravity upwards, without changing the track width. While the center of gravity increases, generally, in every vehicle when loaded, the agency compared the increase in center of gravity in 15-passenger vans to other multipassenger vehicles. On average, the center of gravity in a 15-passenger van increased by 4 inches, whereas it only increased by 1.4 inches in a seven-passenger van and 0.9 inches in a minivan. NHTSA estimates that the change in center of gravity can increase the rollover propensity in these vehicles by as much as 40 percent.

The copyright of the article 15-Passenger Vans May Present Rollover Risk in Defective Products is owned by . Permission to republish 15-Passenger Vans May Present Rollover Risk in print or online must be granted by the author in writing.