Car Seat Testing and the Swedish Plus Test

All car seats that are for sale in Europe have passed the standard ECE R129 or R44/04 tests. Some have gone through additional testing by the ADAC, and many of the rear facing car seats that are available on this website have passed the Swedish Plus Test.


ECE R44/04

These tests have been used since the 1980s and the current revision is 04, so the orange sticker on the seat will say R44/04 or show an approval number that starts with 04.

R44/04 testing includes a frontal impact at 32mph, a rear impact at 18mph. and a roll over simulation test. There is no mandatory side impact test. The buckle and harness are tested repeatedly to ensure they can take the stress and strain of everyday use, the buckle is tested to ensure it takes a certain force to open and that it can still be opened even when the harness is fully tightened around the child. And there are additional assessments done on ease of fitting and use, and on the instructions.


The way R129 car seats are crash tested is more or less the same as the R44 tests, with the addition on a side-impact test at 15mph.
The biggest difference is the dummies that are used. R44/04 uses the older style P-dummies, whereas for R129 the more advanced Q-dummies are used.

P and Q-dummies

In the late 1970s and early 1980s the P-dummies were developed, they are a series of child crash test dummies from newborn to ten years. The P-series have four sensors, in the head, neck, spine and abdomen. They are still used for EU regulation ECE R44 and also for other standards, such as the US one.

In 1993 the International Child Dummy Working Group started developing the Q-series of child dummies as successors to the P-series. The Q-dummies differ considerably from the P-dummies. Not only do they have 32 sensors to represent the human body and how it moves far more accurately, they were also made to be used in both front and side impact testing, making them the first multi-directional child dummies.


Twice a year the German Motoring Organisation, the ADAC, carries out crash tests on many new car seats that are available in Europe. The ADAC uses Q-dummies and tests car seats at higher speeds than the standard R44 and R129 tests. The frontal crash test is done at 40mph and the side impact test at 31mph.

The ADAC also tests car seats for ease of use and child comfort, and this can lower the overall result even if the seat got a high safety score. The ADAC's website says: "The overall rating only relates to safety and ease of use, with the lower rating tipping the scale". That means that a car seat that has done very well in the crash tests can still get a low rating if the testers consider the seat to be difficult to install, or if they think that the child may be uncomfortable or have a restricted view out of the window.

And the opposite is also true. A car seat that doesn't get a high score in the safety tests, but is easy to install and looks comfortable, gets a higher overall rating based on its ease of use and comfort results. And that overall rating doesn't reflect the fact that the safety result may not have been very high.

Which? Magazine uses the ADAC results in the car seat ratings they publish every year.

The P-dummies that are used in R44 testing are not capable of measuring neck loads, and although R129 and the ADAC do use Q-dummies, the neck loads are not taken into account. This explains why some forward facing car seats get a higher ADAC rating than some rear facing ones, and why R44 car seats can be used forward facing from 9kg. If neck load measurements were used, the ratings would be very different. The tests that forward facing car seats pass don't show the high neck loads, and therefore they don't only appear to be safer than they actually are, but also the safety benefits of rear facing go completely unnoticed.

Swedish Plus Test

The Swedish Transport Institute (VTI) perform an additional test called the Swedish Plus Test. Its predecessor, the T-Standard Test was first developed in 1975, seven years before R44 car seat tests were mandatory in Europe. This makes Sweden the world leaders in car seat testing.

The Plus Test is a frontal impact done at 56.5kmh/35mph and uses a shorter braking distance than other tests, making the impact even more severe. It uses the more advanced Q-dummies and is the only car seat test in the world that measures the loads on the child's neck. In all forward facing car seats the loads on the neck are higher than the safe maximum. This is why only rear facing car seats can pass the Plus Test. Car seats that are forward facing or have a forward facing option are not tested because they are not expected to pass.