The New IIHS Small Overlap Offset Test

The full story is here: http://www.iihs.org/externaldata/srdata/docs/sr4706.pdf

On August 14, 2012, the IIHS released a small overlap offset test. Their moderate overlap test, conducted since 1995 and formerly simply known as the "frontal offset" test, involves a car striking a barrier at 40 mph, with 40% of the front end on the driver side. The new small overlap test reduces the percentage to 25%. This video will explain everything:
The first round of releases consisted of 11 low-end luxury cars. Think BMW 3 series, Mercedes C class, and others in its category. IIHS grades by a demerit system: more demerits equals worse performance and higher injury risk to a real person. I have calculated these demerits as best I could using http://www.iihs.org/ratings/protocols/pdf/small_overlap_rating_protocol.pdf and the individual section ratings for each model. Here goes.

0-3 demerits is good, 4-9 is acceptable, 10-19 is marginal, and 20+ is poor. Maximum is 74.

Accurate to August 16, 2012

2009-12 Acura TL - 2 demerits - Good rating

Although the structure was only rated acceptable, a tight seatbelt and supportive front, side torso and side curtain airbags kept the occupant's movement in check away from any hard structures. The driver dummy's head hit the frontal airbag and grazed the side curtain airbag, while the side torso airbag kept the chest from moving toward the door. All body parts were well protected.

2011-12 Volvo S60 - 2 demerits - Good

The structure was markedly stronger than even the TL's, with virtually no intrusion into the cabin. Volvo's independent small overlap testing since the early 1990s has paid off. Alas, it did still score two airbag related demerits; the frontal airbag was judged to be too narrow, allowing the head to slip between it and the side curtain airbag. The side curtain airbag was judged to be slightly undersized, not covering area far forward enough. The side torso airbag deployed late. Still, with no injury, the Volvo S60 came away with a good.

2007-12 Infiniti G - 6 demerits - Acceptable

The structure on this one was rated marginal, with substantial intrusion into the footwell by the wheel. The damage to the occupant compartment was bad enough that the rating was knocked to acceptable. Still, the intrusion was not disastrous, and padding and front, side torso, and curtain airbags that worked nearly flawlessly kept this dummy unharmed.

2009-12 Acura TSX - 16 demerits - Marginal

We enter the bad zone here. The structure on this one was rated marginal, with quite a bit of footwell intrusion. This intrusion caused a high risk of major injuries to the lower leg and foot, such as a fractured tibia or broken ankle. Only the frontal airbag was deployed, and the dummy was completely unprotected from the side; intrusion also caused the steering wheel to be driven to the right, which caused the dummy's head to slip off the frontal airbag and move toward the door. With no other injury risks besides the lower leg and foot, the car still managed a mid range marginal rating.

2012 BMW 3 - 16 demerits - Marginal

The ratings were the same as the Acura TSX, but manifested in a different manner. The marginal structure on this one led to footwell intrusion and upward steering wheel movement as opposed to movement toward the right. Once again, there were major lower leg and foot injuries, despite the presence of a knee airbag. The side curtain airbag did deploy. With three airbag deployments, there were still problems with the restraints. The steering wheel's upward movement left little airbag cushioning for the chest. The side curtain airbag was undersized. The side torso airbag did not deploy, and the seat belt allowed the dummy to move too far forward. With six demerits from structure problems, six from restraint problems, and four from the leg injury, this car found itself in the marginal circle.

2007-12 Lincoln MKZ - 18 demerits - Marginal - Applies only to cars built after January 2007

Ten of the 18 demerits were caused by the structure taking major damage. The footwell was driven back over a foot. The dashboard moved up to 10 inches toward the dummy. It's a wonder the dummy only suffered minor left knee injury, accounting for two more demerits. The last six were from restraint problems. The most dramatic of these was the steering wheel's getting shoved sideways 7 inches, which caused the dummy to completely miss the frontal airbag. That's right, no contact whatsoever. The side curtain airbag, although undersized, and the side torso airbag's deployment salvaged the restraint rating to a marginal and thus kept this car from being sunk to a poor. This car was scored a low-end Marginal.

2009-13 Volkswagen CC - 18 demerits - Marginal

Marginal structure: six demerits. Risk of minor hip and thigh injury: two demerits. But this car was a big spender on the restraint system. Ten demerits were spent for the severe problems found with this car's restraint system. Problem one: the dummy's head moved too far forward due to a too-loose seat belt. Problem two: the steering wheel moved toward the right 8 inches, and the only airbag that did deploy, the driver frontal airbag, was barely touched by the dummy as it slid past it toward the door. Problem three: no side torso or side curtain airbag deployment, leaving the dummy with no protection from the door. Problem four: at the end of the crash, there was no door attached to the car for the driver dummy; it had been completely ripped off just before the car came to a halt.

2010-12 Mercedes C class - 20 demerits - Poor

Our first poor-rated vehicle earned its poor rating. A poor footwell structure was caused by wheel intrusion; the tire was nearly touching the dummy's left foot after it punched through the footwell. Entrapment of the dummy's right foot under the brake pedal resulted from this intrusion. Ten demerits. The poor footwell structure caused the lower legs and feet to sustain forces that would cause major injury to both left and right, and a knee airbag proved ineffective. A marginal restraint system only deployed a front and knee airbag, leaving sides unprotected, and a loose seat belt allowed the dummy to move toward the door. The frontal airbag stayed in contact with the head. The highest end of poor ratings, but a poor nonetheless.

2006-12 Lexus IS - 24 demerits - Poor

The structure of this car got a solid poor. 17 inches of footwell intrusion and 9 inches of dashboard intrusion constituted occupant compartment collapse. This collapse caused major lower leg and foot injury despite a knee airbag. The frontal and knee airbags deployed, but the sides were unprotected. The restraints put on a poor performance. The steering column got shoved 6 inches toward the right, but a massive frontal airbag stayed in contact with the dummy. However, the dummy's head actually moved outside the side window.

2009-12 Audi A4 - 30 demerits - Poor

The structure on this one was not good. 11 inches of footwell intrusion wasn't as bad as some, but 11 inches of dashboard intrusion and 5 inches of steering wheel rearward movement (and 7 of right movement) was among the worst of all cars tested. The lower legs and feet got a break, but the left hip would likely be broken, a more debilitating injury that cost this car ten demerits alone. The restraints were poor. A sufficiently sized curtain airbag deployed, but the praise ends there. No side torso airbag went off. The driver door opened, and that caused an automatic poor for the restraints. A tie for worst performer numerically.

2007-12 Lexus ES - 30 demerits - Poor

In my opinion, this one takes the cake for worst performer. 17 inches of footwell intrusion and 11 inches of dashboard intrusion, 8 inches of steering wheel upward movement and 6 inches of right movement, with the column facing upward at the height of the crash? The structure collapsed. The injury measures were similarly severe - the left leg from the knee all the way down suffered major injury, and the left hip also could get seriously injured. The restraint system also didn't do well. Once again, a complete lack of side airbag deployment.

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