NHTSA New Car Assessment Program ("NCAP ") - Frequently Asked Questions

1. What is NCAP?

In 1978 the New Car Assessment Program (NCAP) in the United States was initiated with the primary purpose of providing consumers with a measure of the relative safety potential of vehicles in frontal crashes. NCAP now supplies consumers with important comprehensive information, including frontal- and side- crash test results, to aid them in their vehicle purchase decisions. The ultimate goal of NCAP is to improve occupant safety by providing market incentives for vehicle manufacturers to voluntarily design their vehicles to better protect occupants in a crash and be less susceptible to rollover, rather than by regulatory directives.

2. Glossary of terms and abbreviations

High Likelihood of Pelvic Injury - Pelvic g's were greater than 130 g's
High Likelihood of Thigh Injury - Thigh (femur) force was greater than 2,250 lbs.
No Data - The instruments used to record the test data malfunctioned.
Seat Too Small - The testing laboratory could not reasonably seat the crash test dummy.
TBT - To Be (Crash) Tested
TBR - To Be Rated; Rollover resistance Ratings are measured based on Static Stability Factor (SSF)
Under Review - The data from this test is being examined for quality assurance. This does not mean the vehicle has an unsatisfactory score.
w/SAB - The vehicle tested was equipped with a side air bag.

3. How do I find information on a specific vehicle?

The easiest way to search for a specific vehicle is to click on one of the icons: a car, truck, van or SUV. On the next page select your vehicle size and year to get all vehicles in that class for comparison, or type in the make, model and year of the specific vehicle. You may also click on the search icon and then search by year or make, model and year.

4. How does NHTSA choose which vehicles to test or rate?

NHTSA chooses new vehicles which are predicted to have high sales volume, vehicles which have been redesigned with structural changes, or have improved safety equipment for testing. These vehicles are purchased from dealerships, just as a consumer would, and not supplied by the manufacturer.

5. How does NHTSA categorize vehicles?

NHTSA classifies vehicles by weight. Passenger cars are categorized as mini (1,500-1,999 lbs. curb weight), light (2,000-2,499 lbs. curb weight), compact (2,500-2,999 lbs. curb weight), medium(3,000-3,499 lbs. curb weight) and heavy(3,500lbs.and over curb weight.) The other categories are sport utility vehicles (SUVs), light trucks and vans.

6. Can I compare vehicles from different classes?

Depending on the weight of a vehicle, it can be compared to other vehicles in it's class. Since a frontal crash test into a fixed barrier is similar to a crash between two vehicles of the same weight, the frontal crash test results can only be compared to other vehicles in the same weight class and those plus or minus 250 lbs.

Side crash test results can be compared across all classes because all vehicles are hit with the same barrier and at the same force.

Rollover Resistance Ratings can also be compared across all classes.

7. How can I compare a Crash-Test Dummy to a real person?

The injury risk curves obtained from the test dummy in the crash demonstrate the probability of injury to a real person in that crash. The risk curves are shown below. The lower the injury number, the less chance that a person would be injured in that crash.

8. How does NHTSA perform frontal-crash test and rate vehicles?

For testing frontal collisions, crash-test dummies are placed in driver and front passenger seats and secured with the vehicle's seat belts. Vehicles are crashed into a fixed barrier at 35 miles per hour (mph), which is equivalent to a head-on collision between two similar vehicles each moving at 35 mph. Since the test reflects a crash between two similar vehicles, make sure you compare vehicles from the same weight class, ± 250 lbs., when looking at frontal crash protection ratings.

Instruments measure the force of impact to each dummy's head, chest, and legs. The resulting information indicates a belted person's chances of incurring a serious injury in the event of a crash. In the explanation of ratings below, a serious injury is one requiring immediate hospitalization and may be life threatening.

9. What is the difference between a full frontal test and an offset crash test? Does NHTSA do both?

NHTSA's NCAP Program crashes the full width of the front of a vehicle into a rigid barrier. This maximizes the energy absorbed by the front of the vehicle so that the occupant compartment is more likely to remain intact. The full frontal tests produce high level occupant compartment decelerations, making them very demanding of the restraint systems, thus providing better information on the safety features and their performance.

In offset crash tests, like those performed by the Insurance Institute of Highway Safety (IIHS), only one side of a vehicle's front end is hit, thus a smaller area of the structure absorbs the energy from the crash. Offset crashes are more demanding on the structure of a vehicle, and intrusion into the occupant compartment is more likely in these crashes.

NHTSA is conducting research on offset frontal crash tests.

10. How does NHTSA side-crash test and rate vehicles?

For testing side impact collisions, crash-test dummies are placed in driver and (driver's side) rear passenger seats, on the side of vehicle struck, and secured with the vehicle's seat belts. This test represents an intersection-type collision with a 3,015 pound barrier moving at 38.5 mph into a standing vehicle. The barrier is covered with material that has "give" to replicate the front of a vehicle. Since all tested vehicles are impacted by the same size barrier, it is possible to compare all vehicles with each other when looking at side crash protection ratings.

Side-collision star ratings indicate the chance of a life threatening chest injury for the driver, front seat passenger, and the rear seat passenger. Head injury is not measured in these tests. As with the front-impact ratings, a serious injury is one requiring immediate hospitalization and may be life threatening.

11. Why are there fewer side crash test ratings?

NHTSA was not authorized to side crash-test vehicles until1997. We began with model year 1997 cars, then in 1999 started testing light trucks, sport utility vehicles and vans. NHTSA does not side crash-test vehicles over 6,000 lbs. (per FMVSS 214) as these vehicles are generally considered to be commercial vehicles.

12. Why doesn't NHTSA do rear impact crash tests?

Since the NCAP Program has a limited budget, funding is concentrated on front and side impact crashes which are responsible for the highest percentage of deaths and serious injuries. A relatively small percentage of deaths or severe injuries are associated with rear impact crashes.

13. Why isn't NHTSA testing my vehicle?

NHTSA selects vehicles for testing and/or rating based primarily upon sales volume. Since not all vehicles can be tested, those with smaller sales volume may not have been selected. Only NHTSA rates vehicles on rollover resistance, but your vehicle may have been crash tested by another source. Try searching IIHS, EURO NCAP, NRMA or Japan's web site at the following addresses:

http://www.hwysafety.org/vehicle_ratings/ratings.htm

http://www.fia.com/tourisme/safety/safint.htm

http://www.nrma.com.au/

http://www.osa.go.jp/

14. If NHTSA didn't test my vehicle, how do I know if it's safe?

All vehicles sold in the United States must pass Federal Motor Vehicle Safety Standards (FMVSS) including a compliance crash test which is a 30 mph frontal impact test and a 33.5 mph side impact test.

15. Does NHTSA have crash data on vehicles made before 1990?

NCAP began frontal crash tests in 1979, so there is crash information available on vehicles staring that year. Information prior to 1990 is archived, and is not listed on the web. This data is available to consumers. Send an e-mail to crash.test@nhtsa.dot.gov with the year, make, and model of the vehicle to obtain the crash information.

16. How do I get more detailed crash data and rollover measurement data?

An electronic version of vehicle crash test reports from 1999 to present, and details of measurements for rollover ratings can both be downloaded from the DOT docket at http://dms.dot.gov.

To use the system you must input a docket number. Details of measurements for rollover ratings can be found in Docket #8298. All 1999 to present frontal NCAP vehicles can be found at Docket #4962 and all 1999 to present side NCAP vehicles can be found at Docket #3835.

A vehicle and occupant curve for all crash tests can be found in the OCR database. You can access the database through the Research and Development link on NHTSA's home page.

For a fee, all NCAP vehicle reports and films are available from the National Crash Analysis Center. Please contact them at 20101 Academic Way, Ashburn, VA 22011, Tel.(703)726-8226 FAX (703)726-8358.

17. What is a "Rollover Resistance Rating"? Most rollover crashes occur when a vehicle runs off the road and is tripped by a ditch, curb, soft soil, or other object causing it to rollover. These crashes are usually caused by driver behavior such as speeding or inattention. These are called single vehicle crashes because the crash did not involve a collision with another vehicle. More than 10,000 people die each year in all rollover crashes.

The Rollover Resistance Rating is an estimate of your risk of rolling over if you have a single vehicle crash. It does not predict the likelihood of that crash. The Rollover Resistance Rating essentially measures vehicle characteristics of center of gravity and track width to determine how "top-heavy" a vehicle is. The more "top-heavy" the vehicle, the more likely it is to roll over. The lowest rated vehicles (1-star) are at least four times more likely to roll over than the highest rated vehicles (5-stars).

The Rollover Resistance Ratings of vehicles were compared to 220,000 actual single vehicle crashes, and the ratings were found to relate very closely to the real-world rollover experience of vehicles.

While the Rollover Resistance Rating does not directly predict the risk of injury or death, keep in mind that rollovers have a higher fatality rate than other kinds of crashes. Remember: Even the highest rated vehicle can rollover, but you can reduce your chance of being killed in a rollover by about 75% just by wearing your seat belt.

Here are the Rollover Resistance Ratings:

In A Single Vehicle Crash, a vehicle with a rating of:

18. Why is consumer information for vehicle rollovers necessary?

While rollovers do not occur as frequently as other types of crashes (see Figure 1), when they do occur, the result is often serious injury or death. Rollovers accounted for more than 10,000 fatalities in the United States in 1999, more than side and rear crashes combined (see Figure 2). They also resulted in thousands of serious injuries. NHTSA believes that most of these rollovers, and the tragic injuries that result, are preventable, if consumers understand the roles the driver, roadside environment and vehicle play in causing the rollover.

19. How do most vehicle rollovers occur?

From its studies of real-world single-vehicle crashes, NHTSA has determined that more than 90% of rollovers occur after a driver runs off of the road (see Figure 3). This does not refer to vehicles trying to negotiate difficult trails away from public roads. It refers to vehicles rolling over off of the pavement after the driver has lost control of the vehicle. Once the vehicle slides off of the pavement, a ditch, soft soil, curb or other tripping mechanism usually initiates the rollover.

20. How should I interpret NHTSA'S Rollover Resistance Ratings?

The Rollover Resistance Ratings are based on Static Stability Factor, which is essentially a measure of how top heavy a vehicle is. The Rollover Resistance Ratings of vehicles were compared to 220,000 actual single vehicle crashes, and the ratings were found to relate very closely to the real-world rollover experience of vehicles. Based on these studies, NHTSA found that taller, narrower vehicles, such as sport utility vehicles (SUVs), are more likely than lower, wider vehicles, such as passenger cars, to trip and roll over once they leave the roadway. Accordingly, NHTSA awards more stars to wider and/or lower vehicles. The Rollover Resistance Rating, however, does not address the causes of the driver losing control and the vehicle leaving the roadway in the first place.

21. Does a vehicle with a higher Rollover Resistance Rating mean it is immune from rollovers?

No, even a five-star vehicle has up to a 10 percent risk of rolling over in a single vehicle crash. In fact, because of the aggressive way in which the vehicle is driven and/or the age and skill of the driver, certain five-star vehicles such as sports cars, may have a higher number of rollovers per hundred registered vehicles than certain three-star vehicles, such as mini vans, due to the fact that they are in more single vehicle crashes.

22. How does Electronic Stability Control affect rollover, and what is its relationship to the Rollover Resistance Ratings?

Electronic Stability Control ("ESC"),which is offered under various trade names, is designed to assist drivers in maintaining control of their vehicles during extreme steering maneuvers. It senses when a vehicle is starting to spin out (oversteer) or plow out (understeer), and it turns the vehicle to the appropriate heading by automatically applying the brake at one or more wheels.

Some systems also automatically slow the vehicle with further brake and throttle intervention.

What makes ESC promising for rollover prevention is the possibility that with its aid many drivers will avoid running off the road and having a single vehicle crash in the first place. However, ESC cannot keep a vehicle on the road if its speed is simply too great for the available traction and the maneuver the driver is attempting, or if road departure is a result of driver inattention. In these cases, a single vehicle crash will happen, and the rollover resistance rating will apply as it does to all vehicles in the event of a single vehicle crash.

23. What can I do to reduce the chance of a rollover?

A rollover crash is a complex event, heavily influenced by driver and road characteristics, as well as the design of the vehicle. Consequently, a consumer should also know that:

All Vehicles Can Roll Over

• All types of vehicles can roll over in certain conditions. While SUVs have the highest number of rollovers per 100 crashes (see Figure 4), because of the higher numbers of passenger cars on the road, almost half of all rollovers which occurred in 1999 involved passenger cars (see Figure 5).
  
  Rollovers Are More Likely on Rural Roads and Highways
  

• When a vehicle goes off rural roads it is likely to overturn when it strikes a ditch or embankment or is tripped by soft soil (see Figure 6). Many other rollover crashes occur along freeways with grassy or dirt medians when a driver loses control at highway speeds and the vehicle slides sideways off the road and overturns when the tires dig into the dirt (see Figure 7).

Since most vehicle rollovers are single-vehicle crashes, they are often preventable. They are unlike non-rollover multiple-vehicle crashes involving frontal, side and rear impacts, where another driver may have been responsible for the crash. To minimize the risk of a rollover crash and serious injury, the driver should: