The Future Of I-Size Law: When Will It Be Enforced?

The i-Size regulation (ECE R129) is a European-wide car seat regulation that aims to make car seats safer. It was introduced in 2013 and uses the child's height to determine if the seat is suitable, rather than their weight. It was implemented to standardise and make child car seats easier to fit, as they all use the Isofix system, which attaches the car seat directly to the frame of your car using built-in connectors. While there is no set date for when i-Size will become law, it is likely that the law will eventually only allow R129 seats to be sold.

i-Size seats are based on a child's height, not weight

The i-Size car seat regulation, also known as ECE Regulation 129 or R129, is a new European-wide car seat regulation that launched in 2013. The i-Size regulation runs alongside the older Regulation 44 (R44) but does not replace it.

I-Size car seats are based on a child's height rather than their weight. Height is a better gauge of how well your child will fit in the seat. While age and weight are still helpful factors, height makes it easier to see when it's time to move up a seat. i-Size seats come in three different sizes, with rough equivalents within the weight-based sizing system:

• 0-85cm (approximately G0+ in the weight-based system) – rear-facing baby carrier or baby seat using a harness
• 0-105cm (approximately G0/1/2) – rear-facing baby seat until your child is at least 76cm, then forward facing
• 100-135cm (UK)/150cm (ROI) (approximately G2/3) – forward-facing child seat

I-Size seats aim to reduce the confusion around car seat suitability. Under the older regulations, car seats were categorised by weight, but parents often don't know the weight of their child. As a result, they end up matching weight with age, which is not always accurate as one 9-month-old baby may have a very different weight to another. With i-Size, parents can simply measure their child's height regularly and match it to the appropriate car seat.

i-Size seats are rear-facing until the child is at least 15 months old

The i-Size is a new European regulation that aims to make car seats safer for children. It is the first phase of a safety standard called R129. The i-Size regulation does not replace the current R44/04 law but runs alongside it. This means that you can still use your current car seats and manufacturers can still sell non-i-Size seats until at least 2018, as long as they meet the old regulations.

One of the key changes under the i-Size regulation is that children will be rear-facing for longer. Specifically, i-Size requires children to sit rear-facing until they reach at least 15 months of age. This is a longer period than what was advised under the previous regulations, which recommended that children sit rear-facing only until they weigh 9kg.

The reason for this change is that studies have shown that rear-facing car seats offer significantly more protection in the event of a car accident. Swedish research found that rear-facing car seats can provide up to 75% more protection for young children in car accidents. This is because, in a head-on collision, the forces of impact are distributed more evenly across a child's body in a rear-facing seat, reducing the pressure on their head and neck. A child's neck is not fully developed until they are at least 15 months old, and in a forward-facing seat, the excessive pressure on their neck during a collision could lead to serious neck injury.

The i-Size regulation also addresses the issue of side impact protection. While car seats previously only had to be tested for protection in accidents where the front or back of the car is hit, they now legally require side impact protection as well. Additionally, i-Size seats can only be attached using ISOFIX anchorage points, which reduce the risk of incorrect installation, a common problem with car seats.

i-Size seats have passed a side-impact test

The i-Size regulation is a new European-wide car seat regulation, which is the first phase of a safety standard called R129. It aims to make car seats safer by keeping children rear-facing for longer, providing better side impact protection, and making car seats easier to fit correctly.

One of the key features of the i-Size regulation is its focus on side-impact protection. Under the older regulations, car seats were only required to be tested for protection against accidents where the front or back of the car was hit. However, i-Size now legally requires car seats to ensure side impact protection, as studies have shown that it is safer for children to remain rear-facing until they are at least 15 months old.

To comply with the i-Size regulation, car seats must pass a rigorous side-impact test. This test replicates a 30-mph T-bone-style side collision, which is commonly known as a "T-bone crash". The test uses a sliding vehicle seat mounted on rails, known as a sled, and a vehicle door mounted on the sled to resemble the vehicle. During the test, child seats will be evaluated using the Q3s side impact test dummy, representing a 3-year-old child, along with the CRABI 12-month-old child test dummy.

By passing this side-impact test, i-Size seats provide better protection for children in the event of a side-impact collision. The test ensures that the car seats prevent harmful head contact with an intruding vehicle door and reduce crash forces transmitted to the head and chest during side-impact collisions. This is crucial, as side-impact collisions account for a significant number of car accident fatalities among children under 8 years old.

In summary, the i-Size regulation's inclusion of a side-impact test ensures that car seats provide enhanced protection for children in side-impact collisions. By requiring car seats to pass this rigorous test, parents can have greater peace of mind knowing that their children are safer in the event of a side-impact crash.

i-Size seats can only be attached using ISOFIX anchorage points

The i-Size car seat regulation is a new European-wide child car seat regulation, also known as ECE Regulation 129 or R129. It does not replace the previous Regulation 44 (R44) but runs alongside it. This means that parents can choose to buy and use child car seats that meet either R44.04 or R129 (i-Size seats).

One of the key changes that i-Size introduces is that it requires the use of ISOFIX anchorage points to attach the car seat. i-Size seats cannot be installed using adult seat belts. This is because ISOFIX reduces the risk of installing the seat incorrectly, which is the biggest safety problem around car seat use. Evidence suggests that up to 75% of car seats are not fitted correctly when using a seat belt, compared to 94% of parents who use ISOFIX correctly.

ISOFIX is an internationally standardised car seat safety system. It automatically locks your car seat, or the base of the car seat, into two ISOFIX fitting points. The seat is essentially ‘plugged’ into these fixed points rather than fastened in using a seatbelt, which can make it easier to install and less likely to be installed incorrectly. An additional top tether or support leg can prevent the child seat from tilting or rotating in the event of a collision.

All new cars sold in Europe since late 2014 have been required to come with ISOFIX fittings, but many older cars also have the system. Cars manufactured from 2011 come with ISOFIX as standard. If your car is older than this, you may be able to buy an ISOFIX conversion kit. The kit costs around £17 and can be fitted in about an hour for about £90. However, it’s worth noting that the older a car is, the less likely it will be compatible with the kit. Any cars made before 1997 won’t be able to accommodate any i-Size car seat.

To check if your vehicle has i-Size approved seating positions, you should first consult your vehicle handbook. If your car doesn’t have any i-Size approved seating positions, you may still be able to use an i-Size child restraint on seats with ISOFIX anchorage points. This is only if the vehicle and seating position are included in a vehicle-specific application list, supplied by the child restraint manufacturer. If you plan to use your child seat in more than one vehicle, it’s important to check that all have i-Size approved seating positions or appear on a vehicle-specific application list.

i-Size seats can be used in any 'i-Size approved' seating position

The i-Size regulation (ECE R129) was introduced in Europe in 2013 and uses the child's height to determine if the seat is suitable, rather than the child's weight. It was introduced with the intention to standardise and make child car seats easier to fit—as they all use the Isofix system, which attaches the car seat directly to the frame of your car using built-in connectors.

I-Size seats can be used in any i-Size-approved seating position and must be installed according to the car manufacturer's instructions. Check your vehicle handbook first to see if any seating positions are i-Size-approved (not available in cars registered before July 2013).

If your car doesn’t have any i-Size-approved seating positions, you may still be able to use an i-Size child restraint on seats with Isofix anchorage points. This is only if the vehicle and seating position are included in a vehicle-specific application list, supplied by the child restraint manufacturer.

If you plan to use your child seat in more than one vehicle, it’s important to check that all have i-Size-approved seating positions or appear on a vehicle-specific application list.

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