1.Newborn to 15 months (shorter than 76 cm)
Use an infant carrier, rear-facing only. The large shell supports the still-developing neck and head. Prefer ISOFIX rigid connectors (two anchor points) to limit forward rotation. Recline the seat 45°to 60°to keep the airway open and prevent injury under hard braking.
2.About 1 to 4 years (76 to 100 cm)
Choose a convertible seat that allows both directions. Keep it rear-facing until at least 18 months and 76 cm; the egg-shaped shell spreads crash forces. After 18 months you may turn it forward.
Belt install: route the lap-and-shoulder belt through the guides below the head-rest; belt-to-seat angle below 60°to stop slippage. ISOFIX install: drop the support leg to the floor to create a solid triangle.
3.About 4 to 12 years (100 to 150 cm)
Switch to a high-back booster, forward-facing with its 5-point harness. Deep side wings limit forward movement.
If the car has ISOFIX, click the seat in and extend the back-set adjuster so the shell hugs the vehicle seat for extra stability and comfort.
If no ISOFIX, thread the vehicle belt through the booster’s shoulder guide so it sits flat on the collar-bone, free of neck pressure.
4.About 6 to 12 years (125 to 150 cm)
Use a booster cushion or high-back booster plus the vehicle’s 3-point belt. The pelvis is still small; the booster raises the child so the lap belt crosses the thighs, not the abdomen.
Place the booster flat on the rear seat, set vehicle back-rest 110°to 120°, and check that the child’s whole back contacts the cushion so the belt cannot ride up and bruise internal organs.
5.Universal rules
Prefer the centre rear position (43 % lower injury risk). If no ISOFIX there, use an outboard seat with matching anchors.
After install, push the seat: forward/rear movement must be no more than 2.5 cm. For rear-facing, ensure the support leg sits flush on the floor with no wobble.
Inspect ISOFIX clips and tether every 3 months; replace any clip that has lost spring tension.