TOP > Child Seat Assessment > Useability of Child seat
New Car Assessment Japan
Safety Information Group

3-2-1 Kinshi, Sumida-ku,
Tokyo 130-0013
Phone: 03-5608-7560
[Weekdays 9:15 a.m.~5:30 p.m.]
E-Mail : admin@nasva.go.jp

Useability of Child seat

Types of Child seat

(targeted stature and age are only rough ideas)

■For Infant
Mass of targeted infant is 10 kg or less or 13kg or less, stature is 70 cm or less and age is up to 1 year old.
For infant, there are bed type and rearward facing type.


■For toddler (forward facing only)
 Targeted child is mass of 9 to 18kg, stature is 65 to 100 cm and age is 1 to 4 years old. However, there is one CRS covering for infant and toddler (so call usage for both infant and toddler).


■For school children
The CRS for targeted child for 15 to 36kg masses, stature is 135 cm or less and age for 4 to 10 is existing. However, CRS assesment is not included this category.
The perpose of this CRS is lifting up child hip to adjust adult hip position and may use adult seatbelt.
Reason not to include this CRS for the assesment is that performance of this type CRS is grearly influenced by the vehicle seat belt performance.

Effectiveness of CRS usage

To obsreve usage and none usage of CRS in trafic accidents, threre are great difference for fatality rate and fatal and serious injuries rate in between when CRS is used and when CRS is not used.

Technical regulation of Child seat

There are 2 types of indications that are Type approval mark and Type designated mark, and which are met Japanese safety regulation.
Child seat safety requirements are reviewed in October 2006, and stand point of international harmonization of the regulations, this regulation was harmonozed with R44(4th revision) under United Nation's 1958 Agreement.

Compatibility with the vehicle

Some of the CRSs cannot fit some type of the vehicles.
Please reffers and confirms CRS manufacturers' recommendation chart which are explain fitness to the vehicles, and then select proper CRS to fit for your vehicle.

Fitting method to the vehicle

Fitting method of CRS is differ from the products, therefore, please follow the instruction manual when you install your CRS to the vehicle.
Al most all CRS in the market are fixed to the vehicle using vehicle seatbelt, and there are 2 types that are 2 points fixing type and 3points fixing type based on seatbelt passing methods.

3 points fixing method using 3 points seatbelt

Types of CRS fixing device to the vehicle

Vehicle seatbelt

2 points type seatbelt
This type is used for front center seat or rear center seat. But many CRS in the market is not used for 2points seatbelt. However, revision of seatbelt and seatbelt anchorage requirements in October 2006, new passenger vehicle (under 10 passengers) and truck (GVM 3.5 ton or less) shall be equiped with 3points sestbelt from July 2012.

3 points type seatbelt
Seats other than seat with 2 points seatbelt installation are installed 3 points sestbelt. And retracting device for seatbelt are ELR specified below and etc.

ELR type (Emergency Locking Retractor) seatbelt
Seatbelt is freely pulling out normaly, but only when the shock is received, such as a sudden braking, this seatbelt has a device to lock.

ELR type seatbelt with CRS fixing mechanism with the combination of ALR (Automatic Locking) )
Normaly, ELR mechanism is activated, but when seatbelt is pulled out total length of the belt, the mechanism is changed from ELR to ALR and activate to pull in direction only and not to pull out at that time. This type can easily fixed CRS tightly.

Warning
Don't child play with seatbelt. The mechanism may change to ALR and if the belt is tangled with child neck or body, it will be happened serious injury such as a suffocation, due to belt cannot loosen. In the case of an emergency, and not to unfasten the belt, you should cut the belt by the scissors.

Common Fixing device (ISOFIX)

CRS fixing device for ISOFIX is installed in the vehicle seat. The CRS for ISOFIX specified by the every vehicle is used with the conbination of the vehicle seat. The requirements for the CRS is reviewed in October 2006,may permit to use CRS for universal type ISOFIX with the combination of the tether strap. The vehicle is neccessary to install universal type ISOFIX anchrage.

Vehicle with a built-in CRS

Normally, CRS is built in the vehicle seat (normally rear seat), and may use as the CRS after pulling out from the vehicle seat when child is on boad. Now a day, some imported vehicle has the CRS for school children (so call junior seat) as a optional equipment.

vehicle with a built-in CRS

Pay attention when CRS is installed

●Install in rear seat
In the case airbag is installed for the front passenger seat, it is very dangerous to install reaward facing CRS in the front passenger seat, Therefore, strictly prohibited to do so.

●Fix tightly
CRS shall be fixed tightly followed by users manual guidance. In the case of forward facing CRS, CRS shall be fixed tightly not to move (roughly around 3 cm or less) when force is applied for frontal direction on the top area of the CRS. In the case of the vehicle that has the seatbelt with CRS fixing mechanis (normaly, left and right side of rear sests), after installing CRS, vehicle seatbelt is fully pulling out and be activated ALR mechanism.

Advice:In the case seatbelt stopper is existing, it will be well done to use seatbelt stopper after CRS is loaded and vehicle seatbelt is pulled out to fix CRS by lap belt only.

●Be carefull not to burn when child is sested
When the vehicle is parked under the flaming sun, CRS itself, buckle and metal parts of seatbelt became very hot and possibly be burned. Before child seat on the CRS, you shall be confirm to tatch mentioned parts.