Car Safety: IIHS

Correlation of IIHS Moderate Overlap Offset Rating with 2011-Present NHTSA Injury Risk Score, Over Time

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Note: I am not affiliated with the NHTSA or IIHS, or am even an engineer. I am a 22 year old with Asperger's Syndrome who is very interested in car safety.</div>
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This post is not intended to endorse one rating system over the other.</div>
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Explanations of tests and injury criteria:</div>
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The IIHS moderate overlap offset test, introduced in 1995, involves crashing a vehicle into a deformable offset barrier at 40 mph, with 40% of the front end on the driver's side, using a Hybrid III 50th percentile male dummy (about 5'10 and 180 lbs) belted into the driver's seat. Vehicles are rated on six categories; structure/safety cage (how much the occupant compartment collapsed), restraints/dummy kinematics (how well the seat belts, airbags, and other vehicle parts controlled dummy movement), and four injury subsections: head/neck, chest, left leg/foot, and right leg/foot. The entire body from head to toe is effectively covered. Each of these six categories gets a rating of good, acceptable, marginal, or poor, and these ratings are <a href="http://www.iihs.org/iihs/ratings/technical-information/moderate-overlap-frontal-calculator">combined</a> into a rating of good, acceptable, marginal, or poor.</div>
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NHTSA crash tests vehicles into a flat wall at 35 mph. Vehicles get a rating of 1-5 stars on each side, with the rating being strictly on injury risk to the head, neck, chest, and femur (in effect, the entire body except for the lower legs). The current system, introduced on October 5, 2010 for 2011 model vehicles, uses a formula to determine the risk of serious injury to a real life occupant. It's comprehensive, and it adds up. As an example, the 2011 Honda Accord got a 9.8% risk of driver injury in the NHTSA full frontal test, giving it 5 stars. But that 9.8% is divided into a 0.0% risk of head injury, a 6.6% risk of neck injury, a 2.7% risk of chest injury, and a 0.8% risk of femur injury. The total does not add up to 9.8% because there is a slight chance that multiple body regions could sustain serious injury.</div>
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In late 2010, when the first results for the new NHTSA test results came out, I downloaded a copy of a spreadsheet with the NHTSA tests up to that point. The dummies in the driver's seat of the new NHTSA tests are the same as the dummies in the IIHS offset tests, and all applicable injury measures are in the technical information. (HIC 15, Nij, Neck Tension in newtons, Chest Deflection in millimeters, and femur forces in newtons on each side). On the IIHS website, they give the newtons in kilonewtons; for instance, I put in 1.4 kilonewtons as 1,400 newtons. NHTSA also records neck compression, but it would take extreme values of neck compression to make a difference to the rating, and Nij (neck injury criterion) tends to take care of that factor, anyway.</div>
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Results are given for all tests done during a particular model year. For instance, the 2011 Honda Accord's crash test applies to 2008-2012 models, but is included under the 2008 model year because the tested car was a 2008. Similarly, the 1998 Ford F-150's crash test applies to 1997-2003 models, but is included under the 2001 model year as the tested truck was a 2001.</div>
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9.9% or less = 5 stars</div>
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10.0%-14.9% = 4 stars</div>
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15.0%-19.9% = 3 stars</div>
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20.0%-39.9% = 2 stars</div>
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40.0% or more = 1 star</div>
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For more information, visit</div>
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<a href="http://www.iihs.org/iihs/ratings/technical-information/technical-protocols">IIHS technical info</a></div>
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<a href="http://www.safercar.gov/Vehicle+Shoppers/5-Star+FAQ#thirteen">NHTSA technical info</a></div>
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The formula for the injury risk calculation is at (It is an advanced calculus formula)</div>
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<a href="http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0322.pdf">http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0322.pdf</a></div>
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Data</div>
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Avg injury risk - all vehicles tested during the model year:</div>
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1995: 19.3%</div>
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1996: 23.7%</div>
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1997: 25.7%</div>
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1998: 19.7%</div>
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1999: 20.6%</div>
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2000: 19.8%</div>
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2001: 26.1%</div>
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2002: 18.3%</div>
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2003: 16.0%</div>
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2004: 15.0%</div>
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2005: 15.4%</div>
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2006: 16.2%</div>
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2007: 15.2%</div>
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2008: 17.4%</div>
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2009: 13.4%</div>
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2010: 14.9%</div>
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2011: 12.6%</div>
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2012: 13.3%</div>
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2013: 12.1%</div>
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2014: 11.7%</div>
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2015: 10.8%</div>
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Average risk, 1995-1997: 23.2%</div>
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1995-97 Poor: 26.7%</div>
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1995-97 Marginal: 21.0%</div>
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1995-97 Accept.: 23.9%</div>
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1995-97 Good: 17.3%</div>
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Poor-Good improvement: 36% lower risk</div>
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Average risk, 1998-2000: 20.1%</div>
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1998-2000 Poor: 27.8%</div>
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1998-2000 Marginal: 26.5%</div>
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1998-2000 Accept.: 18.9%</div>
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1998-2000 Good: 15.2%</div>
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Poor-Good improvement: 45% lower risk</div>
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Average risk, 2001-2003: 20.1%</div>
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2001-2003 Poor: 58.6%</div>
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2001-2003 Marg.: 28.5%</div>
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2001-2003 Accept.: 18.8%</div>
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2001-2003 Good: 16.1%</div>
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Poor-Good improvement: 73% lower risk</div>
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Average risk, 2004-2006: 15.6%</div>
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2004-2006 Accept.: 19.1%</div>
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2004-2006 Good: 14.8%</div>
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Conclusions</div>
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The correlation between IIHS rating and NHTSA injury risk score was strong. Good rated vehicles had a much lower risk than Poor rated vehicles, with Marginal and Acceptable being intermediate steps. Due to the low number of non-Good rated vehicles from 2004 and later model years, the comparison was for 1995-2003 vehicles. 94% of vehicles from 2004-present are rated Good. Some caveats to the comparison are the much higher risk on the 2001-2003 Poor rated vehicles than the 1995-2000 Poor rated vehicles. This is due to the small sample size (only 4 different models). However, these four models (the 1997-2003 Ford F-150, the 1994-2001 Dodge Ram, the 2001-2003 Hyundai Elantra, and the 2001 Dodge Caravan) were all high-selling models.</div>
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Also of note was the rather sudden improvement pattern seen from around 2010 on. On pre-2009 vehicles, the average risk for Good vehicles stayed around the 15-17% range. Improvements during these years were largely due to the improvements in the IIHS ratings. With Good ratings nearly ubiquitous since the late 2000s, the improvements seen in the post-2010 period represent major improvements in Good rated vehicles. The 2013-2015 vehicles (all of which have been rated Good thus far) have a 21% lower risk on average than the Good-rated 2004-2006 rated vehicles. (11.7% vs 14.8%). These recent improvements may be due to restraint changes stemming from the implementation of the new 2011-present NHTSA rating system, which is far more stringent than the 1979-2010 system.</div>
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While the correlation was strong, it was not total: the best Poor vehicle got an 11.0% risk, and the worst Good got a 32.1% risk. 23% of vehicles rated Poor got a risk under 20%. Part of this reason is that the NHTSA rating system does not cover tibia injuries, structure, or restraints. That 11.0% risk Poor vehicle (the 1997 Cadillac Seville) is a poster child of this. The structure of this vehicle collapsed, and dummy movement was poorly controlled, leading to Poor ratings on both of those factors. High forces on the right tibia lead to a Poor rating for the right leg. Many of the "low-risk" Poor rated vehicles suffered from a combination of tibia injury risk, structure, and restraint problems. Some vehicles had high head accelerations from the head hitting the steering wheel through the airbag or hitting the roof or pillar on rebound. In many cases, these high accelerations are of very short duration, so they do not result in a high HIC. Life threatening injuries would be unlikely, but these hard contacts can cause less severe head injuries including concussions.</div>
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Another factor is that IIHS does injury ratings "piecemeal"; there are certain force limits that are considered to be "likely" to cause certain levels of injury. If, for instance, a vehicle got Good on all injury ratings but the force levels were all "borderline", i.e. HIC, Nij, neck tension, chest compression, and both femur loads were just under the Good/Acceptable boundary, the injury risk would be high, over 45%. In practice, however, this would never occur. Also, theoretically, a vehicle could have a risk under 10% and get a Poor rating if structure and restraints were Poor and tibia loads were high, but head, neck, chest, and femur forces were all low. This nearly happened, but is extremely unlikely as structural collapse usually imparts higher upper body loads through the restraint system or airbag bottoming out, and dashboard movement often causes higher femur loads.</div>
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Some stock can be put to the risks, especially in Good rated vehicles. For instance, a Good rated vehicle with a risk of 10% is probably safer than one with 20%. But a low "risk" does not a safe vehicle make. Regardless of the risk, the IIHS rating is the best indicator of how well a vehicle will do in an offset crash. It was specifically designed for the crash scenario.</div>

Correlation of IIHS Moderate Overlap Offset Rating with 2011-Present NHTSA Injury Risk Score, Over Time

Note: I am not affiliated with the NHTSA or IIHS, or am even an engineer. I am a 22 year old with Asperger's Syndrome who is very inter...

Trends in HIC, Chest G and injury risk, NHTSA crash tests, 1979-2010

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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9DCbG6iVLNeCOJfhXYtZbpwPJeSF8pcmlJOth5fck4QZlvbLdizPJ8AJljiMoYjg2L1MkVkPk4dz5AQcsXEFmDWQmC1mjHmgGd2OCvVC5R1iW6-tWV7WvKGUDW5fiXB9l9TozBwk3eXD5/s1600/charts+for+csd.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9DCbG6iVLNeCOJfhXYtZbpwPJeSF8pcmlJOth5fck4QZlvbLdizPJ8AJljiMoYjg2L1MkVkPk4dz5AQcsXEFmDWQmC1mjHmgGd2OCvVC5R1iW6-tWV7WvKGUDW5fiXB9l9TozBwk3eXD5/s1600/charts+for+csd.jpg" /></a></div>
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The top chart shows average HIC for each model year of NHTSA crash testing between 1979 and 2010. The improvement is crystal clear, but there are some notes. The early years, specifically 1981-1984, showed a sharp drop in average HIC values for the tests as car companies strove to compete with each other on safety. 1985 saw a spike in HIC, especially for the driver; a large number of light trucks (pickups, SUVs, and vans) were tested this year, and their lower safety standards at the time skewed the results. The second major drop occurred from 1988-1994 for drivers, due chiefly to air bags. The introduction of passenger air bags did not result in a sudden drop in HICs, but gradual improvement continued. HIC improvement was gradual during the 1995-2004 period, followed by a near leveling out from 2005-2010. The leveling out of good results led to the replacement of this test.</div>
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At the very beginning of the test program, passenger HICs were slightly higher, on average; during the 1980s, driver HICs were often significantly higher, likely due to improved seat belt systems and better structures but the continuance of steering column problems. Air bags briefly gave driver HICs the advantage, but passenger air bags caused passenger HICs to become lower again during the 1995-2002 period. Less aggressive driver airbags gave driver HICs the advantage from 2003-2010.</div>
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Chest measures aren't quite as clear cut. The sharp 1981-1982 drop was likely due to improved structures and seat belts, but chest measures rose modestly, plateauing during the 1985-1999 period for drivers, despite the introduction of air bags. Passenger chest measures rose during the 1986-1996 period, despite the widespread introduction of air bags during this time period. A possible explanation is that early air bags were "firmer" and more aggressive than today's airbags, and seat belt pretensioners and load limiters came along in the late 1990s. Chest measures fell during the 2000-2004 period, but leveled out from 2005-2010.</div>
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Injury measures is another odd one. I took the average HIC and Chest G for each side for each model year, and translated that into the injury risk for the "average" vehicle. <b>Your vehicle may vary. </b></div>

Trends in HIC, Chest G and injury risk, NHTSA crash tests, 1979-2010

The top chart shows average HIC for each model year of NHTSA crash testing between 1979 and 2010. The improvement is crystal clear, but t...

Curtain Airbags and the IIHS Moderate Overlap Offset, 2003-2013

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In the 2003 model year, the first vehicles to inflate curtain airbags in the IIHS offset came on the market, and since then, a good number of vehicles have blown the curtains to help keep the driver away from the side of the vehicle.</div>
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In cases of re-tested vehicles, only the final test, applicable to the majority of the production run, is used. All vehicles tested from each model year from 2003 to 2013 are included in the percentages, even those not including curtain airbags, but only for the tested year: for instance, the 2008 Honda Accord's test applies to the 2008-2012 models but is included under the 2008 model year as this is the year it was tested. Convertibles are not included as their design is incompatible with curtain airbags without special engineering techniques.</div>
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Interestingly, many of the earliest driver curtain deployments were in Nissan built vehicles, while many recent Nissans don't deploy a curtain.</div>
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 2003 model year: 78% no curtain, 17% driver curtain only, 6% both curtains. 18 vehicles tested.</div>
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 2004 model year: 90% no curtain, 10% driver curtain only, 0% both curtains. 21 vehicles tested.</div>
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 2005 model year: 96% no curtain, 4% driver curtain only, 0% both curtains. 23 vehicles tested.</div>
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 2006 model year: 86% no curtain, 10% driver curtain only, 5% both curtains. 21 vehicles tested.</div>
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 2007 model year: 73% no curtain, 18% driver curtain only, 9% both curtains. 33 vehicles tested.</div>
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 2008 model year: 71% no curtain, 16% driver curtain only, 13% both curtains. 38 vehicles tested. </div>
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 2009 model year: 45% no curtain, 45% driver curtain only, 10% both curtains. 31 vehicles tested.</div>
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 2010 model year: 75% no curtain, 25% driver curtain only, 0% both curtains. 24 vehicles tested.</div>
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 2011 model year: 31% no curtain, 56% driver curtain only, 13% both curtains. 32 vehicles tested.</div>
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 2012 model year: 44% no curtain, 56% driver curtain only, 0% both curtains. 25 vehicles tested.</div>
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 2013 model year: 27% no curtain, 70% driver curtain only, 3% both curtains. 30 vehicles tested.</div>
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 2014 model year: 22% no curtain, 65% driver curtain only. 13% both curtains. 23* vehicles tested.</div>
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*Tests released on or before March 13, 2014.</div>

Curtain Airbags and the IIHS Moderate Overlap Offset, 2003-2013

In the 2003 model year, the first vehicles to inflate curtain airbags in the IIHS offset came on the market, and since then, a good number ...

Frontal Airbags and the IIHS Moderate Overlap, 2003-2014

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As the last post stated, whether your side curtain airbag deploys in an IIHS style head on collision is based on what car you are in. Barring some major malfunction, the frontal airbag <i>will </i>deploy, if you have a frontal airbag. It's literally a requirement to make a good rating. There's a heck of a lot of force in a 40 mph head on collision. Most frontal airbags are designed to go off in about a 12-16 mph head on collision; a 40 mph collision is 6-11 times that force. In other words, in today's cars, if that frontal airbag doesn't inflate, serious injury or death is likely. If it works properly, you'll likely walk away in a good rated vehicle.</div>
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Frontal airbag non deployment happens very rarely in the IIHS moderate overlap test, and when it does it's as often a fault of test preparation as vehicle malfunction. The final tests are only in the results for each model year: some vehicles had airbag malfunctions that were fixed, such as the 2003 Honda Pilot, which had a late airbag deployment in its first test. The problem was fixed, and in the final test, the airbag worked properly.</div>
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"Bottoming out", where the airbag is insufficiently inflated to prevent hard contact with the steering wheel, does happen more often. Because many vehicles prior to 2003 had poorer structure designs and the curtain post focused on 2003-present vehicles, this post focuses on trends since 2003 on airbags bottoming out. Results are given in "sufficiently inflated" percentages: a "sufficiently inflated" airbag prevented hard contact with the steering wheel. </div>
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2003 model year: 78% of driver airbags were sufficiently inflated, 14 of 18 vehicles tested.</div>
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2004 model year: 62% of driver airbags were sufficiently inflated, 13 of 21 vehicles tested.</div>
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2005 model year: 70% of driver airbags were sufficiently inflated, 16 of 23 vehicles tested.</div>
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2006 model year: 90% of driver airbags were sufficiently inflated, 19 of 21 vehicles tested.</div>
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2007 model year: 79% of driver airbags were sufficiently inflated, 26 of 33 vehicles tested.</div>
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2008 model year: 87% of driver airbags were sufficiently inflated, 33 of 38 vehicles tested.</div>
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2009 model year: 81% of driver airbags were sufficiently inflated, 25 of 31 vehicles tested.</div>
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2010 model year: 75% of driver airbags were sufficiently inflated. 18 of 24 vehicles tested.</div>
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2011 model year: 100% of driver airbags were sufficiently inflated, 32 of 32 vehicles tested.</div>
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2012 model year: 84% of driver airbags were sufficiently inflated, 21 of 25 vehicles tested. </div>
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2013 model year: 90% of driver airbags were sufficiently inflated, 27 of 30 vehicles tested. </div>
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2014 model year: 96% of driver airbags were sufficiently inflated, 22 of 23 vehicles tested to March 30, 2014.</div>
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A noticeable trend has occurred, with fewer airbags bottoming out in the IIHS moderate overlap. From 2003-2005, 69.3% of airbags held the drivers away from the wheel. 2006-2010 had 82.3%, and 2011-2014 92.7%. </div>

Frontal Airbags and the IIHS Moderate Overlap, 2003-2014

As the last post stated, whether your side curtain airbag deploys in an IIHS style head on collision is based on what car you are in. Barri...

In A Side Impact, Do Frontal Airbags Help or Hurt?

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Side airbags have been blowing off in frontal crashes for years now. While some vehicles take the principle overboard, many vehicles are deploying their driver side curtain airbags in the IIHS offset test, due to the side movement. Here's ten reasons that deploying this side's curtain airbags can be a good idea: <a href="http://www.iihs.org/ratings/rating.aspx?id=1374&seriesid=459">1 </a><a href="http://www.iihs.org/ratings/rating.aspx?id=233&seriesid=385">2</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=1681&seriesid=750">3</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=1400&seriesid=710">4</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=811&seriesid=354">5</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=1302&seriesid=427">6</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=1414&seriesid=513">7</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=1602&seriesid=623">8 </a><a href="http://www.iihs.org/ratings/rating.aspx?id=1688&seriesid=322">9</a> <a href="http://www.iihs.org/ratings/rating.aspx?id=1483">10</a></div>
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I'm going to try to settle the question of whether frontal airbags are likely beneficial or detrimental in side impacts. The primary purpose of NHTSA's side impact (from 1994-2010) was to measure thorax injury, so I'm going to compare cars with side and curtain airbag deployments for my control group. I will average the Thoracic Trauma Index for all vehicles with frontal airbag deployment in addition to side airbag deployment, and average the Thoracic Trauma Index for all vehicles with just side and curtain airbag deployment.</div>
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I have a hunch that today's advanced airbags are not harmful to most occupants in side impacts, so I will also compare vehicles with no side airbags and frontal airbag deployment against vehicles with no airbag deployment altogether.</div>
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The side airbag test group will consist of 2008 models for the no front airbag group and 2007-2009 models for the front airbag group. This is to get a larger sample size for front airbag deployments, as they are in the minority.</div>
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The no side airbag test group will consist of 2002 models for the no front airbag group and 2001-2003 models for the front airbag group.</div>
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Individual cases will be used as well.</div>
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For the side airbag (2008) test group:</div>
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Average TTI, no front airbag: <b>44.3 - </b>37 vehicles - Range 18 to 66 with an outlier of 86</div>
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Average TTI, front airbag - <b>40.6 </b>- 14 vehicles - Range 17 to 70</div>
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It is clear that in recent vehicles with side airbags and advanced frontal airbags, front airbag deployment poses little risk and may actually be slightly beneficial. The torsos of all 14 driver dummies were not unduly loaded, and the faces were not hit.</div>
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Front airbag deployment CAN be harmful to a small driver sitting far forward in a side impact, however advanced airbags can mitigate this risk.</div>
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It is also worthy to note that 44.3 and 40.6 are very low TTIs corresponding to a ~1% risk of severe injury. The state of side impact crashworthiness was very good for most vehicles by 2008.</div>
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The no side airbag test group will be in a later post.</div>
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In A Side Impact, Do Frontal Airbags Help or Hurt?

Side airbags have been blowing off in frontal crashes for years now. While some vehicles take the principle overboard, many vehicles are de...

The New IIHS Small Overlap Offset Test

The full story is here: <a href="http://www.iihs.org/externaldata/srdata/docs/sr4706.pdf">http://www.iihs.org/externaldata/srdata/docs/sr4706.pdf</a><br />
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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:</div>
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<iframe allowfullscreen="allowfullscreen" frameborder="0" height="266" mozallowfullscreen="mozallowfullscreen" src="https://www.youtube.com/embed/u2Fzp3f-C0I?feature=player_embedded" webkitallowfullscreen="webkitallowfullscreen" width="320"></iframe></div>
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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 <a href="http://www.iihs.org/ratings/protocols/pdf/small_overlap_rating_protocol.pdf">http://www.iihs.org/ratings/protocols/pdf/small_overlap_rating_protocol.pdf</a> and the individual section ratings for each model. Here goes.</div>
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0-3 demerits is good, 4-9 is acceptable, 10-19 is marginal, and 20+ is poor. Maximum is 74.<br />
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<i><b><span style="font-size: large;">Accurate to August 16, 2012</span></b></i><br />
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2009-12 Acura TL - 2 demerits - Good rating<br />
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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.</div>
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2011-12 Volvo S60 - 2 demerits - Good<br />
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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.</div>
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2007-12 Infiniti G - 6 demerits - Acceptable<br />
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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.</div>
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2009-12 Acura TSX - 16 demerits - Marginal<br />
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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.</div>
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2012 BMW 3 - 16 demerits - Marginal<br />
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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.</div>
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2007-12 Lincoln MKZ - 18 demerits - Marginal - Applies only to cars built after January 2007<br />
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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 <i style="font-weight: bold;">completely miss the frontal airbag. </i>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.</div>
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2009-13 Volkswagen CC - 18 demerits - Marginal<br />
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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 <i style="font-weight: bold;">was no door </i>attached to the car for the driver dummy; it had been completely ripped off just before the car came to a halt.</div>
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2010-12 Mercedes C class - 20 demerits - Poor<br />
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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. <b><i>E</i></b><i style="font-weight: bold;">ntrapment </i>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.</div>
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2006-12 Lexus IS - 24 demerits - Poor<br />
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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.</div>
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2009-12 Audi A4 - 30 demerits - Poor<br />
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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.</div>
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2007-12 Lexus ES - 30 demerits - Poor<br />
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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.</div>

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 of...