10 Safety Checks to Make Before You Buy

From crash tests to child seats, here's what to look for when comparing vehicle safety

When choosing a new car, consider government crash-test ratings, as well as features like head restraints, electronic stability control, and rollover resistance.

There are many factors to consider when evaluating a vehicle's overall safety. They range from how it performs in an emergency-handling situation or protects its occupants in a collision to how easy it is to secure a child seat. When comparing vehicles, it's important to look at all the appropriate variables, including safety-related ratings and features. Below, we list 10 safety checks that are worth reviewing before you make your final buying decision.
1. Government crash-test ratings
The National Highway Traffic Safety Administration (NHTSA) conducts two types of crash tests: full frontal and side impact. Each is scored on a five-star scale, with fewer stars indicating a greater likelihood of serious injury. You can check the scores for all crash-tested vehicles online at www.safercars.gov.

NHTSA's frontal test is a good indication of how well a vehicle's safety belts and air bags protect the occupants in specific types of impacts. The frontal test runs vehicles into a rigid barrier at 35 mph. That simulates a head-on collision between two vehicles of similar weight, each traveling at 35 mph. Instrumented crash dummies in the two front seats record the crash forces they sustain and scores are assigned for the driver and front passenger.

NHTSA's side-impact test simulates a vehicle traveling at 17 mph being hit on the side by a 3,000-pound car traveling at 34 mph. Scores are assigned to the driver and the left-rear passenger.

2. Insurance-industry crash-test ratings
The Insurance Institute for Highway Safety (IIHS) is a safety-research group that conducts its own series of crash tests. In its frontal-offset crash, a vehicle is run at 40 mph into a deformable barrier. Instead of engaging the whole width of the car's front end, the barrier covers just the 40 percent of the car directly in front of the driver.

Using a deformable barrier simulates a car-to-car, driver's-side-to-driver's-side collision, which is a common form of fatal crash. By focusing the crash on only a portion of the car's front, this test severely stresses the car's structural integrity and its ability to protect the area around the driver without collapsing.

The IIHS scores its frontal-crash results as Good, Acceptable, Marginal, or Poor. You can find ratings for all tested vehicles at the IIHS Web site, www.hwysafety.org.

Recently, the IIHS has also begun conducting its own side-impact tests, which simulate being hit by a truck instead of NHTSA's 3,000-pound car. However, many vehicles have not yet been tested.

Both the IIHS and NHTSA crash-test results are comparable only to vehicles within the same weight class as the tested car. If vehicle weights are very dissimilar, the results could be very different.

3. Accident avoidance
A vehicle's ability to help you avoid an accident is just as important as its crashworthiness. Key factors to consider are braking and emergency handling, although acceleration, visibility, driving position, and even seat comfort (which affects driver fatigue) also play a role.

4. Air bags
By law, every new passenger vehicle comes equipped with dual front air bags. But the sophistication of the systems can vary. It's worth checking what type of air-bag systems a vehicle has, both in the front and rear.

Many upscale vehicles now have some version of a "smart" air-bag system. It uses electronic sensors to gauge several variables, which, depending on the model, include crash severity, safety-belt use, the position of the driver's seat, and the weight and/or position of an occupant in the front-passenger seat. This information is used to tailor the deployment of the vehicle's front and side air bags.

Dual-threshold and multi-stage front bags can deploy with varying force, depending on crash severity. In a lower-level collision the bags inflate with limited force. In a more severe crash, the bags inflate with more force and more quickly. Many systems withhold deployment on the passenger side if the seat is unoccupied (to save money on replacement) or if the seat is occupied by a person below a certain weight (to prevent possible injury from the bag).

Side air bags are now common for front occupants. The basic side air bag deploys from the seatback or door, and is designed to protect a person's torso. Separate side bags that protect the head are becoming increasingly available, as well. The most common design is a side-curtain bag that drops down from the headliner and covers both the front and rear windows. Consumer Reports highly recommends head-protection side air bags where they're available.

Side torso air bags are also included in the rear seats of some models, but these can pose a risk for smaller children sitting out of position in the outboard seat positions. In some models, rear side bags need to be activated by the dealer.

5. Antilock brake system (ABS)
CR's auto experts highly recommend getting an antilock brake system (ABS), which is available as standard or optional equipment on most vehicles. ABS prevents the wheels from locking up during a hard stop, something that can cause the driver to lose control of the vehicle. ABS almost always provides shorter stops, but, even more importantly, the system helps keep the vehicle straight and allows the driver to maneuver during a panic stop.

6. Rollover resistance
Taller vehicles, such as SUVs and pickups, are more likely to roll over than passenger cars. According to NHTSA, SUVs have a rollover rate that is two to three times that of passenger cars. In 2002, 61 percent of all SUV fatalities and 45 percent of pickup-truck deaths were the result of a rollover. By contrast, only 22 percent of passenger-car fatalities were because of a rollover.

A taller vehicle has a higher center of gravity, which makes it more top-heavy than one that sits lower to the ground. In a situation where a vehicle is subjected to strong sideways forces, such as in a sudden cornering maneuver, it's easier for a taller vehicle to roll over.

To give consumers a way of telling which vehicles have a higher rollover propensity than others, NHTSA has developed a five-star rating system called the Rollover Resistance Rating (RRR). Until recently, the RRR was based solely on a vehicle's "static stability factor (SSF)," which is determined from measurements of its track width and center of gravity. Because the SSF is based on measurements of a stationary vehicle rather than on a dynamic road test, the rating doesn't account for vehicles' different suspension designs, tires, or the presence of a stability-control system—any of which can make a significant difference. Beginning with the ratings for 2004 models, NHTSA now combines the SSF with a dynamic rollover test performed with moving vehicles.

The RRR is accessible online at www.safercars.gov, but you need to dig deeper than the star ratings to tell how a vehicle performed in the dynamic test. Click on the model name. Scroll down to "Rollover Details" and look under Dynamic Test. The site tells you only whether or not a vehicle tipped up in the test, but not at what speed. Currently, it also lacks data about whether rated vehicles were tested with electronic stability control, described below. We believe that vehicles that tip up in NHTSA's test have a potential stability problem and CR will not recommend them, regardless of their star rating.

7. Electronic stability control (ESC)
Electronic stability control is another safety feature that's highly recommended by CR's auto experts, particularly on SUVs. ESC is designed to help keep the vehicle under control and on its intended path during cornering, and prevent it from sliding or skidding. If a vehicle begins to go out of control, the system selectively applies brakes to one or more wheels and cuts engine power to keep the vehicle on its intended course. On SUVs, stability control can help prevent the vehicle from getting into a situation that could lead to a rollover. While electronic stability control has improved the emergency handling on the vehicles we have tested, it's not a cure-all for inherently poor handling vehicles. Its effectiveness depends on how it is programmed and how it is integrated with the vehicle. It also cannot overcome the laws of physics for out-of-control driving.

Automakers often refer to their stability-control systems by different names, so if it's not clear be sure to ask if a vehicle has electronic stability control. To make it less confusing for the consumer, the Society of Automotive Engineers has asked that all manufacturers use electronic stability control or ESC, as common terminology when referring to their stability-control systems. Consumer Reports supports this announcement, and feels it will help consumers know what they are buying.

A number of studies have been completed and all point to a substantial reduction in accidents and deaths. CR engineers feel that ESC is going to be a major safety feature that may become standard on all cars.

8. Safety-belt features
Three-point lap-and-shoulder belts provide the most protection in a crash, and more vehicles now have them in all seating positions. Many, however, still have only a lap belt in the center-rear position, which allows the upper part of the body to move forward in a crash or panic stop. The comfort of the belts is also important, because some people won't wear them if they're uncomfortable. Some vehicles, for instance, have front belts whose shoulder portion retracts into the seatback instead of the car's door pillar. Their advantage is they move with the seat when the seat is adjusted fore and aft. But they can tug down uncomfortably on the shoulder of someone with a long torso. Microsoft Word: http://www.hardwaresoftwarearticles.com/archive/index.php/f-16.html

Many vehicles include safety-belt pretensioners and force limiters, which work with the air bags to protect you in a crash. Pretensioners automatically take up the slack in the seat belt during a frontal crash, helping to restrain people securely and properly position them for the air bag. Force-limiters relax the safety-belt tension slightly following the initial impact, so they can help absorb some of a person's forward thrust. That helps prevent chest and internal injuries caused by the belt.

9. Head restraints
A car's head restraints are vital for guarding against the whiplash neck injuries that often accompany a rear-end collision. Restraints need to be tall enough to cushion the head above the top of the spine. Many cars' head restraints adjust for height. Look for those that lock in the raised position. Those that do not can be forced down in a crash, losing effectiveness. Many cars' rear restraints are too low to do much good, which Consumer Reports notes in their test reports. The IIHS Web site (www.hwysafety.org) also provides the institute's own head restraint ratings for various models.

10. Child safety
Child-safety seats save lives and should be used until a child is big enough to use the vehicle's regular safety belt. The conventional method of attaching a child seat uses the vehicle's safety belts. Often, incompatibilities between the car's seat and the child seat make a good, tight fit difficult and sometimes impossible. Help and Support: http://www.hardwaresoftwarearticles.com/archive/index.php/f-22.html

All new vehicles now have a universal system called LATCH (Lower Anchors and Tethers for Children) that is designed to make attachment easier and more secure. But the system doesn't work equally well in all vehicles. Consumer Reports has found many cars with the new attachment points sufficiently obscured that even with some of the newest child seats it's not easy to use them. CR comments on the ease of installing child seats in its test reports. But the key is to try before you buy.

Another child-safety consideration is power-window switches. Children have accidentally activated a power window while leaning out and have been killed or injured by the window closing on them. The easiest types to inadvertently trigger are horizontal rocker and toggle switches on the door's armrest, which raise the window when pushed down or to the side. Lever-type switches, which are flush with the surrounding trim and only raise the window when pulled up, are a safer design.

About the Author

Adam Fletcher is the webmaster of Hardware Software Articles http://www.hardwaresoftwarearticles.com .