For motorists seeking greater protection in crashes, test results released Sunday by the insurance industry show the benefits of paying for optional side air bags.
Versions of the 2006 Toyota Prius and six minivans made by DaimlerChrysler AG and General Motors Corp. that were evaluated without side air bags got poor marks in side-impact tests.
The same vehicles, when tested with the optional air bags, all showed improvements, and the Prius earned the Insurance Institute for Highway Safety's top score in side protection.
Some 96 percent of Prius models are sold with the side air bags, Toyota Motor Corp. spokesman John Hanson said. The option costs $650.
DaimlerChrysler's minivans — the 2006 Dodge Grand Caravan and Chrysler Town & Country — improved from the worst score to the second-highest on a four-tier scale (poor, marginal, acceptable and good) when the air bags were included. The air bag option costs an additional $595.
GM's four minivan models built on the same platform — the 2006 Chevrolet Uplander, Buick Terraza, Pontiac Montana SV6 and Saturn Relay — showed minor improvements when the side air bags were included, moving up one notch, to marginal.
In testing the Uplander with and without side air bags, the institute said the middle-row seats either dislodged or separated partially from the floor.
Bob Lange, GM's executive director for structure and safety integration, said that "in the 10 years this basic structure has been in use for these vans and their predecessors, we know of no cases in which a rear seat became detached in a side impact."
The side air bags are available for $350 on the minivan models, according to GM's Web site.
In addition to the GM and DaimlerChrysler models, the Mazda MPV and Ford Freestar without optional side air bags received the lowest scores in side protection.
Several small cars tested received the lowest score in side evaluations: Volkswagen New Beetle, Suzuki Aerio, Hyundai Elantra, Kia Spectra, Saturn Ion, Suzuki Forenza, Suzuki Reno and these models without side air bags — Chevrolet Cobalt, Ford Focus, Mazda 3, Mitsubishi Lancer, Toyota Corolla and Nissan Sentra.