A 2011 Honda Accord gets frontal impact testing by the NHTSA
As fatalities on American roadways continue to fall, it goes without question that our cars continue to become safer with each model year. While automotive manufacturers are always trying to improve their products, much of these improvements have come through crash testing.
In the United States, cars are crash tested by just a couple of different organizations:
- The National Highway Traffic Safety Administration (NHTSA). NHTSA is a unit of the United States Department of Transportation (US DOT). There are three branches of government in the United States, and the NHTSA, as part of the US DOT, is within the executive branch of the federal government. There are fifteen executive departments within the U.S. federal government, and each of them reports directly to the president of the United States.
- The Insurance Institute for Highway Safety (IIHS). IIHS is a not-for-profit organization that was founded to reduce deaths, injuries and property damage in the United States. IIHS is supported by a large number of auto insurance carriers.
Short Histories: The NHTSA and IIHS
The history of the NHTSA really began with the passage of two pieces of legislation: The National Traffic and Motor Vehicle Safety Act of 1966, and the Highway Safety Act of 1966. That legislation made the manufacturing of automobiles a regulated industry for the very first time, and established the National Traffic Safety Bureau (NTSB).
The NTSB lasted less than a year before Congress pulled the plug and established the National Highway Safety Bureau (NHSB). And since the third time is often considered the charm, Congress passed the National Highway Safety Act of 1970, which saw the formation of the NHTSA as a re-constitution of the previous NHSB.
The IIHS actually predates the NHTSA. It was founded in 1959 in a joint effort of major insurance associations. Their mission was to basically cheerlead the highway safety efforts of others. After ten years of this, the IIHS was reconstituted as a fully independent entity with a goal of researching, via true scientific process, the ways and means of reducing crash losses – including the loss of human life.
Two Different Organizations: Two Different Crash Testing Standards
While it may seem to be a positive that there are two very different organizations that carry out automotive crash testing, the reality is that they perform very different tests, and results from one cannot be compared to the other. They use different testing procedures, and different rating systems, which can lead to consumer confusion.
Another area for potential consumer confusion is the fact that not all makes and models are tested. Both the NHTSA and the IIHS put emphasis on the cars that are the highest volume makes and models. But important thing for consumers to recognize is that the two organizations standards, testing and ratings just do not match up.
The IIHS conducts the following testing protocols:
- 40 mph frontal offset crash tests
- Side crash tests
- Rollover ratings
- Rear crash/head restraint
- Bumper evaluations
Compare those to the NHTSA, which conducts these testing protocols:
- Full frontal, head-on crash tests
- Side crash tests
- Rollover ratings
The testing protocols look very similar, but in reality, they are very different. The IIHS frontal crash testing utilizes an offset – meaning it only crashes half of the front of the car. The NHTSA, however, crashes the entire front of the car. Two very different tests produce two very different results. The IIHS test is considered to be closer to a real-world example of how the majority of frontal impact collision accidents happen than the NHTSA’s version.
Side crash testing between the two organizations is different as well. While both the NHTSA and IIHS utilize sleds that were designed to mimic the mass and weight of a real car, neither does testing with sleds designed to mimic the greater mass and weight that trucks and sport utility vehicles (SUVs) have. Since an object with greater mass will have more inertia, the failure of either organization to conduct real world testing – how many times have you seen an SUV in a wreck involving a compact car – is troubling.
The real difference in the two organization’s side crash testing is in what they measure. The IIHS has always measured head trauma to drivers and/or passengers in their side crash testing. The NHTSA didn’t begin to measure this until the 2011 model year. In every year past, the NHTSA only measured potential injuries through trauma of occupant torsos.
The other “common” testing between the IIHS and the NHTSA would be rollover ratings – but again, these are very different tests, with very different results. The NHTSA simply rates the chance of a rollover occurring using a mathematical equation based on a car’s center of gravity and other factors, while the IIHS actually tests the ability of a car’s roof to sustain the impact of a crush test involving four times the weight of the car being tested.
Different Tests Mean Different Scores, Too!
U.S. Transportation Secretary Ray LaHood, when announcing the changes to the NHTSA’s testing procedures for the 2011 model year said, “More stars equal safer cars.” And that’s the gist of the NHTSA’s scoring system – a range of results from one to five stars for each of the three tests they conduct, along with an overall vehicle score that combines results from the front crash testing, side crash testing and rollover resistance.
The IIHS utilizes a completely different scoring standard, based on four distinct scores for each test: Good, Acceptable, Marginal and Poor. While these scores are a bit more intuitive than the star rating system employed by the NHTSA, they, like the NHTSA’s scores, offer nothing but a generic look without much detail.
Despite the confusion of multiple testing entities who utilize completely different testing protocols as well as results scoring, we do encourage you to check out both the NHTSA and IIHS testing results when you’re shopping for a new car. We might prefer the IIHS and their real-world based testing over the NHTSA’s, but we discount neither.
But we also encourage you to look beyond these crash test results and look for active safety measures on your new vehicle as well, such as stability control, traction control, and collision warning systems. And of course, do your part and drive safely as well.
