August 21, 2017

The evolution of car safety testing: Side Impact

In the past cars had very little or nothing in the way of side impact protection – the only barrier between the occupant and the colliding car being a thin sheet of door metal. Unsurprisingly the chance of death or serious injury in a side impact crash was very high.

As we saw from the article Frontal Impacts, car safety has historically had a low priority – and up until 1997  – cars were still being tested by the archaic 1974 concrete block test. Unsurprisingly then, up until very recently, there was no legislation on how cars should be tested for side impacts.

Below: Cars in the 1980s and early 90s had very poor side impact protection

Back in the 1980s and early 1990s, the only cars offering any form of side impact protection, were Volvo and Saab. These manufacturers advertised the use of steel safety cells and side impact bars. Volvo also pioneered their own side impact protections system, SIPs, which is still in use to this day.

SIPS works by dissipating the force of the crash throughout the cars structure. Additionally, steel tubing in the front passenger seats are connected to a central crumple zone located in the centre of the car, by the handbrake) which is designed to collapse. All of this means the whole car absorbs the force of the impact, rather than just the door.

Volvo Led the way in side impact safety

Once safety began to help sell cars, in the mid 1990s other manufacturers such as Vauxhall and Ford then began offering some models with side impact protection beams. However there was no conclusive way of knowing whether any of these cars actually were capable of withstanding side impact crashes. It wasn’t until the introduction of systematic crash testing by Euro NCAP in 1997 that the public had access to this information.

As technology increased new occupant restraint systems were introduced. Cars became available with front airbags for the driver and passenger, then side protection airbags for the torso and head. The combination of stronger car bodies and advanced occupant restraint systems – such as airbags –  have helped to make cars much more capable of protecting occupants in side impacts collisions.

The Euro NCAP Side Impact test:

Euro NCAP simulates this type of crash by having a mobile deformable barrier (MDB) impact the driver’s door at 50 km/h. The injury protection is assessed by a side impact test dummy, in the driver’s seat.

Euro NCAP side impact

Accident patterns vary from country to country within Europe, but approximately a quarter of all serious-to-fatal injuries happen in side impact collisions. Many of these injuries occur when one car runs into the side of another or into a fixed narrow object such as a tree or pole.

To encourage manufacturers to fit head protection devices, pole test may be performed, where such safety features are fitted. Side impact head or curtain airbags help to protect the head and upper torso by providing a padding effect and by preventing the head from passing through the window opening. In the test, the car tested is propelled sideways at 29kph (18mph) into a rigid pole. The pole is relatively narrow, so there is major penetration into the side of the car.

Since 2009, Euro NCAP releases an overall rating for each tested vehicle, with assessments in Adult Occupant Protection, Child Protection, Pedestrian Protection and Safety Assist. Euro NCAP also releases information on Electronic Stability control fitment and results of seats and head restraints, put through Rear Impact (Whiplash) testing.

For more information on the tests, visit EuroNCAP

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