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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 Rollover Resistance Rating (RRR). Until recently, 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 SSF is based on measurements of a stationary vehicle rather than on a dynamic road test, rating doesn't account for vehicles' different suspension designs, tires, or presence of a stability-control system—any of which can make a significant difference. Beginning with ratings for 2004 models, NHTSA now combines 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 star ratings to tell how a vehicle performed in dynamic test. Click on 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 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 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, system selectively applies brakes to one or more wheels and cuts engine power to keep vehicle on its intended course. On SUVs, stability control can help prevent vehicle from getting into a situation that could lead to a rollover. While electronic stability control has improved emergency handling on 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 vehicle. It also cannot overcome 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 consumer, 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 most protection in a crash, and more vehicles now have them in all seating positions. Many, however, still have only a lap belt in center-rear position, which allows upper part of body to move forward in a crash or panic stop. The comfort of 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 seatback instead of car's door pillar. Their advantage is they move with seat when seat is adjusted fore and aft. But they can tug down uncomfortably on 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 air bags to protect you in a crash. Pretensioners automatically take up slack in seat belt during a frontal crash, helping to restrain people securely and properly position them for air bag. Force-limiters relax safety-belt tension slightly following initial impact, so they can help absorb some of a person's forward thrust. That helps prevent chest and internal injuries caused by belt.
9. Head restraints A car's head restraints are vital for guarding against whiplash neck injuries that often accompany a rear-end collision. Restraints need to be tall enough to cushion head above top of spine. Many cars' head restraints adjust for height. Look for those that lock in 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 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 vehicle's regular safety belt. The conventional method of attaching a child seat uses vehicle's safety belts. Often, incompatibilities between car's seat and 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 system doesn't work equally well in all vehicles. Consumer Reports has found many cars with new attachment points sufficiently obscured that even with some of newest child seats it's not easy to use them. CR comments on ease of installing child seats in its test reports. But 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 window closing on them. The easiest types to inadvertently trigger are horizontal rocker and toggle switches on door's armrest, which raise window when pushed down or to side. Lever-type switches, which are flush with surrounding trim and only raise window when pulled up, are a safer design.
Adam Fletcher is the webmaster of Hardware Software Articles http://www.hardwaresoftwarearticles.com .