GUIDES - Introducing i-Size

Introducing and explaining the new I-SIZE car seat standard

Introducing I-SIZE

In summary:

I-Size (ECE R129) is the new EU standard that offers better protection if you have an accident. it was developed using the latest research into child safety. The i-Size regulations are designed to provide children with additional protection and safety in the car.
I-size logo

Why do I need I-SIZE?

Lots of parents are moving their children from rear facing car seats to forward facing car seats too early. The danger of doing this is that in the event of an accident, baby’s neck isn’t fully developed or strong enough to support a heavy head which can lead to spinal injury. Keeping baby rearward facing for longer is a much safer way to travel.

I-SIZE Key Points

  1. I-size uses Isofix, which has less chance of being incorrectly fitted than belted car seats.
  2. Length/Height of child classification instead of weight, makes choosing the right car seat easier.
  3. I-Size car seats will fit all i-Size certified cars and almost all cars with Isofix anchors.
  4. Mandatory rearward facing travel for children up to 15 months old.
  5. i-Size conducts side impact testing as standard, improving protection for your child’s head and neck.
  6. Introduces Q-dummies, a new series of advanced crash test dummies which represent children better and provide more information


What is I-SIZE?

Jane Crash Test Research CenterEvery year 700 children die on European roads and 80,000 end up injured. This is a morally unacceptable figure for society and the European economy. 

The fact that the results are so poor, despite the generalised use of Child Restraint Systems that comply with safety standard ECE R-44, emphasises the social importance of continuous research into child safety.

In spite of the many initiatives adopted in Europe, the progress made in child safety over the last decade can be considered negligible, especially in comparison to the advances made in terms of protecting adult passengers over the same period.

The new regulations mean that Child Restraint Systems are significantly safer than those of safety standard ECE R-44, dating back to the 1990s.



How does the new i-Size regulation improve safety?

The i-Size safety standard is designed to improve protection and safety based on 6 significant points:


Universal Integral Isofix

Jane Grand car seat, i-size readyThe i-Size standard requires restraint systems to be installed in the car using Isofix anchors + an anti-rotation system (top tether or support leg). With the i-Size standard it is no longer allowed for safety seats to be installed using the vehicle seat belts. This prevents a considerable percentage of CRS misuse. In some cases installation errors put the child’s safety at great risk, according to the Jané-RACC study ….


Classification By Height

The R-44 standard made classification somewhat confusing, based on Groups, to determine which safety seat to use and led to seats being changed prematurely. i-Size abandons the previous CRS classification using weight groups and instead uses a new classification system that is easier to understand as it is based on the child’s height in cm.

Car Safety Seats and Car Compatibility

The i-Size standard has been developed together with car manufacturers to ensure full compatibility between the CRS and the car. An i-Size CRS is 100% compatible with an i-Size vehicle seat.


Rearward Facing Up To 15 Months At Least

Many parents change their baby’s seat for a forward facing one too soon, in general when the child is round about 9 months old or weighs 9 kg due, in part, to the confusion caused by the ECE R44 standard recommendation.

Under the i-Size standard, forward facing CRS may only be used once the child is 15 months old, although it is recommended to keep the baby in the rearward facing position for as long as possible. This increase is necessary because the baby’s neck is not developed enough to support the weight of the head, which is proportionately bigger than an adult’s head, and this leads to a risk of injury in the event of a head-on impact.

Side impact test


Side Impact Crash Test

Protection in the event of side impact. According to the European CASPER study 27% of accidents involving CRS are side impact collisions. The ECE R44 standard does not define any assessment criteria for side impacts. Because of this high percentage, we need to check that Child Restraint Systems offer sufficient protection against this type of impact. That’s why the new i-Size standard adds side impact tests to the traditional frontal and rear impact tests. 


New Advanced Q Series Dummies, New Criteria

The crash test dummies designed in the 70s (P series) have been phased out. The new dummies (Q series) have been designed in line with the real life sizes of the current population, with materials that reproduce lifelike behaviour better and they are also fitted with new sensors that detect the different stresses on vulnerable parts.

After the numerous studies carried out by the European Vehicle-Safety Committee it was decided to introduce the use of these new dummies that are more biomechanical with greater biofidelity and to introduce new criteria for assessing injuries in the case of frontal and side impacts. New readings were also recommended for injuries to the head, neck, chest and abdomen. The new Q dummy family is able to reflect these types of injuries, due to their biofidelity characteristics and performance and they can also measure the impact in terms of these sections of the body.

For Jané the introduction of the new i-Size standard offers an opportunity to carry on incorporating advances in safety, to carry on researching with greater precision (the new Q series dummies give more detailed information and offer greater biofidelity) and it also, very significantly, means we can carry on raising awareness and encouraging a change in behaviour with regards the installation and use of safety seats”.

Jané works incredibly hard and puts a lot of resources into creating this awareness and changing habits with its educational programmes (Jané Educa) and its continuous studies regarding child mobility.


How can parents recognise an i-Size CRS?

Under the new regulation, the safety seats will indicate the guideline height and age range of the seat user. This makes it easier to choose the correct safety seat for the child and makes it easier for parents to see when they need to replace their safety seat.

The safety seat and the vehicle will also be marked with a specific i-Size label.



When does this new regulation come into effect?

The new i-Size regulation came into effect on 9th July 2013. This new regulation will run in parallel with the current 44/04 standard until round about the end of 2018. It is not expected to come into force for vehicles until June 2014. This new regulation will run in parallel with the current R44/04 standard until round about the end of 2018.

The first vehicles compatible with the i-Size will come out at the end of 2013 and from 2014 more models will be introduced.

For the 5 years following the approval of the i-Size regulation, manufacturers can decide under which regulations they wish to have their seats approved.

Seats approved under the new i-Size regulation may not be approved under Regulation R44/04, in other words, one product may not be approved under both regulations.



Will Jané have i-Size seats when this new regulation comes into force?

Jané will have i-Size seats when the vehicles adapted to this new regulation come out.

The first seats with these characteristics will be the Gravity,  Grand, i-Koos and i-Matrix i-Size seats.

Differences between ECE R44/04 & I-Size (R129)

i-Size (R129) ECE R44/04 Comments
Frontal, rear and side-impact tests Frontal and rear-impact tests but NO side-impact tests I-size introduces a new test, which covers one of the most common types of accidents.
Compatibility with i-Size cars Compatible with the cars indicated by the
CRS / Car Restraint System manufacturer.
List of Automobiles
The i-Size regulation has been developed by
vehicle and CRS / Car Restraint System manufacturers together
Isofix (top tether/support leg) only Car seat can be fixed to car using seat belt or isofix I-size promotes the use of Isofix, which has easier and safer installation.
Up to 33kg (seat + occupant)
Indicate maximum weight of occupant
Max. Weight of the CRS / Car Restraint System 15Kg Max. Weight of occupant 18 Kg. Current i-Size limit equivalent to Group 0-1 of
the ECE R44/04
Classification of car seat is based on height Classification of car seat based on weight The height of the occupant is more representative than the weight.
Baby must stay rear facing until 15 months or 71cm Baby must be rear facing until 9 Kg. (approx. 10 months). I-size promotes the use of rear facing safety seats for longer, at least 15 months old.
Isofix height adjustable support leg 255 mm Isofix height adjustable support leg 140 mm Longer isofix support leg to cover special vehicle circumstances (storage compartments)


Crash Test

Crash Test Differences

R129 i-Size R44 Comments
Frontal crash test Frontal crash test  
Rear crash test Rear crash test  
Side crash test   I-size introduces a new test, covers one of the most common types of accidents.


32 sensors for more advanced results


4 sensors for detailed results

Q-dummies, a new series of crash test dummies that represent children better and provide more information.
Data analysis for:
  • Head
  • Neck
  • Chest
Data analysis for:
  • Chest
Increased protection for vital parts