The overriding function of Child Restraint Systems is to protect children in the event of a collision, preventing them from being thrown out of their seats and cradling their bodies while protecting their heads and necks. Their main objective, therefore, is to save lives. Any approved model meets with minimum safety standards and we, as parents, know what to do and how to position the CRS without making mistakes in order to offer the maximum protection.
However, being officially approved should not be the only measure of the quality of a child seat in that the the final finish can make a huge difference. From a user perspective, an ISOFIX anchor point is better than using just a seat belt as it avoids any potential positioning errors; a booster seat with a backrest and side protectors is better than a simple cushion as it provides increased protection; and equally it is better for a booster to have under-seat belt guides for the abdominal strap of the seatbelt.
In its efforts to identify the best car seats on the market, Euro NCAP (the European program for assessing car safety), regularly refines its crash tests with smaller-sized dummies that represent children. This is a continuous process, and although pretty much the same dummies have been used for the last twenty years, the advances made in sensors and the measurements taken have made a huge quantitative leap forward.
But the truth is that the dummies used up until now do not succeed in offering a true reflection of the kinematics of a child during a crash, especially if we are talking about pressure on the abdomen at the moment of the collision.
At the 14th International Conference Protection of Children in Cars, in Munich, a number of studies were presented that had focused on studying the impact on the thoracic and abdominal areas of children when using different CRS. The study that stood out was the one by Visvikis and Krebs, which described the UMTRI positioning procedure, aimed at improving measurements taken from dummies sat on booster cushions.
The objective of the UMTRI procedure is to improve the way in which the abdominal protection provided by booster cushions is assessed. As a result of the process, the posture of the test dummy changes, and at the same time the seat belt tension is reduced during its installation.
With the new dummies introduced into the test process, called Q3 (bigger and with improved sensors), it is easier to measure the levels of pressure in the abdominal area that hitherto had not shown up in the results, and also to discover that booster cushions with impact shields can increase the risk of chest injuries to children.
Furthermore, in with conventional booster seats, if there is no guide for the abdominal strap, there can be an increased risk of abdominal injuries, partly due to the strap slipping from the child's pelvis up to the abdomen. This can happen through poor positioning or through the child shifting position during the car journey leading to poor posture at the moment of impact.
All of these advances and new tests are essential for the continuous improvement of car seats and better protection of children.