i-Size is part of the latest child car seat regulation ECE R129 that will launch in three phases.
Phase 1, is for children up to 105cm and includes an integral restraint, such as a five-point harness launched in 2013.
Currently, this regulation is running alongside child car seat regulation ECE R44.04 which is an older yet still valid car seat safety regulation.
Eventually, ECE R129 will phase out ECE R44 and be the only legal child car seat regulation, however a definite date is yet to be confirmed.
ECE R129 will eventually become the only regulation that you will be able to approve a car seat to. However, older models of R44.04 car seats will still be legal to use.
The primary goal of ECE R129 (i-Size) is to keep children safer in the car, by making child car seats easier to choose, fit and use.
What are the key changes?
Mandatory rear facing to 15 months
Under the older R44 regulations, children can legally forward face in car seats when they weigh 9kg.
However, with R-129 this is not the case, and children must be rearward facing until 15 months in i-Size seats. This is because it is a safer way to travel, and it is recommend to keep your child rear facing for as long as possible.
This is because young children are at most risk of neck and spinal injuries in the event of a collision due to the size of their head in relation to their body and their developing muscles and bones. This makes them much more vulnerable to serious injury than older children and adults.
i-Size seats require children to be rear facing to at least 15 months old, a point when a child’s neck is stronger and more able to cope with the forces applied during an impact when facing forward.
i-Size addresses the frequent problem of compatibility between R44 regulated ISOFIX car seats and many vehicle makes and models.
From July 2013, car manufacturers were able to have i-Size seating locations approved. Although in the first few years only a few cars had this feature, today nearly all newly designed cars have i-Size seating positions. You can identify i-Size seating locations by the label on the vehicle seat or in the vehicle handbook.
The benefit of an i-Size approved seating position in a vehicle, is that an i-Size car seat is automatically compatible.
You can still use an i-Size car seat in a standard ISOFIX car, however you must always check the vehicle compatibility list first.
Seats selected by height
ECE R44 child car seats are defined by a child’s weight. An approximate age is often also stated but this intended as very rough guidance only.
However, this combination does sometimes cause confusion and can lead to a child being moved to the next stage child car seat before they are ready and their safety can then be compromised.
i-Size makes it simpler for parents to get the selection right as it is defined by the height of the child and mandating rear facing for the first 15 months.
A maximum weight limit will also apply to each child seat and this will be shown clearly approval label attached to the product.
R129 i-Size car seats are selected by the child’s stature. i-SIZE restraints are selected by your child’s height, and each i-Size seat will carry an individual maximum child weight limit. R44 child seats will continue to be chosen by weight, stipulated by defined “group stages”.
Side impact test
You may be surprised to read that ECE R44 does not require child car seats to undergo a side impact test.
Although not legally required, some manufacturers already do this but it is not apparent to the consumer from the ECE R44 product labelling.
To ensure an enhanced level of safety and clarity, all i-Size child car seats undergo a rigorous side impact crash test and so provide a high level of protection in the event of a side impact.
Child seats will be easier to use
i-SIZE phase 1 specifies that child seats must be installed with the ISOFIX mounting system.
ISOFIX establishes a stable connection between the bodywork and the child seat, and minimises the risk of incorrect installation in the vehicle.
Note: there is an exception for infant carrier which may have a belt routing.
A Better Fit For Longer
Unlike ECE R44, the internal dimensions of an i-Size seat will be specified and these dimensions will relate to the latest size data for European children.
i-Size Car Seat Example
The Britax Römer Trifix i-Size conforms to the ECE R129/01 car seat regulation (i-Size) and is suitable for children from 76 cm to 105 cm tall (15 months up to approx. four years), making it the perfect follow up to your infant carrier.
The Trifix i-Size not only provides optimum safety technologies, but also makes sure that children are travelling in comfort with advanced ergonomics of a good seating position and padding.
This seat offers three recline options and a headrest which provides seven height positions to ensure that the seat will grow with the child. Find out more