In the video, which was filmed at Britax's facility in Andover, Hampshire, the two types of car seat are shown side by side in a crash simulation, with a child-size dummy sat in each.
Upon impact, the dummy on the right, which is sat in a highback booster, is held securely in the seat, and is pulled back upright, whilst the dummy on the left in the booster cushion is thrown forward, and can be seen hitting its head on the side of the car as it slips free from the three-point seatbelt.
Mark Bennett, Britax's safety expert, said: 'After watching this footage, parents will think twice when choosing a Group 2-3 car seat as it is incredibly haunting and really demonstrates the importance of deep protective side wings, head support and seat belt guides to ensure that seat belts are correctly positioned and fitted.'
'We are calling for all parents using booster cushions to switch to a highback booster option and help us further spread the word about the inadequate protection these cushions provide.'
Highbacked boosters and booster cushions are the two options available to parents choosing what is known as Group 2-3 car seats, for children weighing between 15-36kg (usually aged between 4-12).
The video aims to highlight the difference in the outcome of a crash with dummies in two different styles of booster seat
According to official government laws on car seat safety, children must use a child car seat until they’re 12 years old or 135cm tall, whichever comes first.
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The guidelines say that booster seats should only be used by children who are 15kg-25kg, and booster cuishons should only be used by children over 22kg. The Britax website explains that it could be the position of the seat belt causing the potential danger. 'Many parents opt for a simple booster cushion to help lift their child and ensure the vehicle seat belt sits correctly on the bony parts of their bodies.'
'However, Britax found that approximately half (49%) of seat belts used to secure child seats may be fitted incorrectly. They are often twisted, too high, or fitted around the seat and not the child. On top of misfittings, these booster cushions also offer no head or side impact protection for children.'