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Safety sells cars like never before. Twenty years ago most new car buyers were content to choose between alloy wheels and a sunroof, and mull over the merits of different colour schemes, but these days we're just as likely to base our buying decisions on the ability of a car to protect us should the worst happen. And that decision is made easier by the EuroNCAP crash tests, which provide easy-to-follow star ratings separating the safe from the so-so. But while the star ratings make it easy to pick a car that performs well in an accident, it inevitably simplifies the picture. To choose wisely you need to delve a little deeper, to find out how the tests are performed and just what the results really mean. First published in CarBuyer, 2004 How EuroNCAP crash tests cars - and how to interpret the results What is EuroNCAP? All cars have to pass crash tests before they are allowed to go on sale, but EuroNCAP - the European New Car Assessment Programme - goes a step further. Based in Brussels, EuroNCAP is an independent body which since 1996 has carried out testing which is more stringent than the legal minimum so that the crash performance of new cars can be compared. The cars are tested in standard form, and EuroNCAP picks the best-selling model. Manufacturers can, if they wish, pay for additional tests on optional safety equipment such as side air bags, but the EuroNCAP ratings are based on the standard car. The tests are carried out on EuroNCAP's behalf by several European crash test labs, including the Transport Research Laboratory in Berkshire. Four different tests are performed, none of which involves towing a car into a concrete block. In the front impact test, carried out at 40mph (64km/h) the car strikes a deformable aluminium barrier which it overlaps by 40 per cent on the driver's side - more representative of real-world accidents than the older 'head on' crash test into an unyielding barrier. Where appropriate the car will be tested with manufacturer-approved child seats fitted, one for an 18-month-old and another for a 3-year-old. Around a quarter of all serious injuries in cars occur through side impacts, so two side impact tests are part of the EuroNCAP programme. The main test uses a trolley with a deformable front end, which is towed into the car at 30mph (km/h). Recently a 'pole test' has been added, where the car is propelled sideways into a rigid pole at 17mph (29km/h), simulating an impact with a tree or telegraph pole. The cars are also rated for pedestrian safety in a 25mph (40km/h) crash by testing several impact zones at the front of the car. Each car is awarded points for its performance in the tests, and these scores are then translated into star ratings for front/side impacts, pedestrian safety and child safety. For instance, the front and side impact scores (out of a possible 34) are added together and extra points are awarded for certain types of seat belt reminder systems, and then if the total is 33 points or more the car is awarded five stars. A total of 25 to 32 points gets four stars, and so on. If the car's scoring is not reasonably even between front and side tests, its rating is reduced. Interpreting the results The star rating system is a good indicator of each car's crash performance, and it's all many people want to know. But reducing such a complex subject to such a simple rating inevitably means there are compromises and simplifications. One problem is that the tests are evolving all the time, with additional tests added and methodology changed. So some older results, particularly those for pedestrian safety, are difficult to compare with the latest round of tests. And not every car is tested, so you may find the model you're interested in doesn't appear in the EuroNCAP results. Another problem is that the ratings can only be compared within their groups. A bigger, heavier car will always survive better in any given accident than a smaller, lighter car: a Skoda Fabia and a Peugeot 607 both score 26 points in the front and side crash tests, but like any bigger car the Peugeot will cope better in most real-world accidents. The child safety ratings provided by EuroNCAP are even more limited, applying only to the combination of vehicle and child seat tested. The same vehicle with a different child seat is likely to perform very differently, and likewise the same seat in a different vehicle will yield different results. Then there's a problem introduced by the star rating itself. Two cars with the same star rating can offer different crash performance: Ford's Focus C-MAX scores 30 for front and side impacts, while the Ford Fusion only scores 24 - yet both are 'four star' cars. Conversely, two cars with different star ratings can offer quite similar protection. The Mitsubishi Shogun Pinin gets three stars, while the Nissan X-Trail wins the same number of points in the crash tests but gets four stars - simply because it earns two extra points for a seat belt reminder. To get the most out of the EuroNCAP result you need to look beyond the star ratings, to the points awarded, which is what we've done for the safety rankings published alongside: the cars are ranked by adding up the points awarded for the EuroNCAP front and side impacts. We've chosen to ignore extra points for seat belt reminders, on the grounds that in the UK we are required by law to wear belts so reminders should be unnecessary. Where two cars tied, the car we've ranked higher is the one with the more even spread of crash protection ability in different areas. We've also picked the best car in each class for pedestrian safety (though almost all cars could be better in this department) and child safety, based on the EuroNCAP scoring. We've looked at all the cars tested so far to compile these tables, including the very latest crash test data released in June (see 'Latest Results' for a summary). All the information for all the cars tested is available on the EuroNCAP website. Conclusion EuroNCAP tests are the best available way of assessing new car safety. Studies in Sweden have shown that, in general, cars with higher EuroNCAP ratings offer a better chance of avoiding serious injury, so it certainly makes sense to look at these safety ratings when you're choosing your next car. Better still, compare the cars you're choosing between by looking at the points scores rather than the star ratings, to get a better idea of the differences between them. The good news is that as well as making crashworthiness information readily available to consumers, the EuroNCAP programme is encouraging car makers to design safer cars: look through the results and you can see clear improvements between older cars and the new generations of models that have superseded them. Which means cars are getting safer - for all of us. Superminis Small family Large family Executive Roadster Large off-roader Small off-roader Small MPV MPVs Drive SafelyBefore you start:
On the road:
Making cars safe: the science bitIt's not enough simply to build a very strong car. In a collision an unyielding structure simply stops, leaving the occupants of the car to fly around inside and sustain injuries. Instead, modern cars are based around the concept of the 'safety cell' and the 'crumple zone', created by Mercedes-Benz engineer Béla Barenyi in the 1950s. The passenger cabin is strongly constructed so that it does not deform in a crash, but the front and rear of the car are designed to crumple progressively to dissipate the energy of the collision. The car sacrifices itself to protect you. In recent years this basic concept has been refined with the addition of side-impact structures in the doors and supplemented by airbags which inflate automatically (using a small explosive charge) when sensors detect a collision. The first airbags were those in centre of the steering wheel, followed by passenger and side airbags. The latest variation is the 'curtain' airbag which inflates across the side windows, lessening the effects of a side impact. Many cars are also fitted with seat belt 'pre-tensioners', which pull the bottom end of the belt down towards the floor in during a crash to pull the belt tight. Latest testsEuroNCAP released details of its latest round of tests in June, including the first test of a hybrid car, the Toyota Prius. The Toyota was one of eight cars to receive a five-star award, and also won top marks for child protection. All the latest large and small family cars tested won five stars, suggesting that new cars are safer than ever.
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