How long should kids stay in child safety seats?

As if it's not bad enough that parents are installing child safety seats incorrectly, many parents are subjecting their kids to danger by using inappropriate safety restraints.

A survey by Melbourne's Royal Children's Hospital has found that the majority of kids aged between seven and 10 travel in cars without the benefit of a booster seat.

According to the hospital's National Child Health Poll, up to 63 per cent of kids that age are at risk. If the kids are sitting too low, and the lap/sash seatbelt restrains the occupant at the neck rather than across the chest, the child could be left with severe spinal injuries after a bad crash.

“Children aged seven to 12 years old are being left vulnerable to life-threatening injuries from car crashes due to inadequate use of car restraints and travelling in the front seat of the car,” said RCH National Child Health Poll Director, Dr Anthea Rhodes.

Based on the findings of the survey – which polled over 1600 parents or guardians – the RCH recommends that parents leave kids in booster seats until the child has reached the height of 145cm. At that point, the car's standard lap/sash seatbelt and airbags (where fitted) will protect the child as well as they would protect an adult.

But up to that point, the RCH strongly insists parents should be placing a booster seat underneath the child.

The law is not actually best practice, according to the hospital. Kids as young as seven can be restrained by an adult lap/sash belt, but are not required by law to be supported by a booster seat. According to the hospital, lap/sash belts are designed for adults at least 145cm in height, and most kids don't reach that height before the age of 11, the hospital advises.

“It’s critical to measure your child before transitioning them out of a booster seat into an adult seatbelt. Booster seats protect children less than 145 cm in height by lifting them up so that the seatbelt fits better cross the chest and hips. Most children don’t reach 145 cm tall until around 11 years of age,” Dr Rhodes was quoted as saying in the hospital's press release.

“This study shows that parents are unaware of best practice recommendations when it comes to car seats and kids. Parents are following the law but unfortunately the law does not reflect safest practice and this means many parents are unknowingly putting their children at risk of serious injury or death every day. A review of Australian laws relating to child car restraints and front seat travel is warranted to address this situation in which current laws may permit, or even encourage unsafe practices.”

Results from the RCH poll indicate three per cent of parents are unaware that children should be using a booster seat if they're under 145cm tall.

Many parents in the past – and no doubt currently as well – have used what the hospital refers to as 'booster cushions', which is a seat base with integrated hooks through which the lap belt passes to hold the base fast in the event of a nose-to-tail or head-on crash. The hospital doesn't recommend the use of a booster cushion because it cannot provide back support for the child and is not anchored properly to the car.

For kids in those intermediate years, the preferred device is a booster seat, which the law demands kids use until the age of seven. The hospital also backs the use of a booster seat, with the qualification that the child should continue to use the booster seat until he or she has reached 145cm tall – or can pass the 'five-step' test.

This test will help a parent determine whether their child has outgrown the need for a booster seat. Can the child sit comfortably with his or her back resting against the seat squab? Can the child do so with his or her feet resting flat on the floor (with knees bent over the leading edge of the seat base)? Does the sash belt cross the child's body at the mid-shoulder region? Is the lap belt positioned comfortably across the top of the thighs? Lastly, can the child comfortably maintain that seating position for the duration of the journey?

Children up to the age of four are required by law to be restrained in a forward-facing car seat, but the RCH advises parents keep their kids in these seats until the child's shoulders have reached the height markers on the seat – and have basically outgrown the seat by then.

For many children, that will be well beyond the age of four, the hospital says.

Children up to the age of six months should be restrained in a rearward-facing car capsule, but once again the RCH advises that the law is out of step with best practice. The hospital recommends that kids up to the age of two years can and should be restrained in a rearward-facing seat, provided their shoulders are below the height markers of the seat.

Once the child's shoulders are at the same height as the markers, the child has outgrown the seat and should move to a forward-facing unit. This could be long after the age of six months.

Half of the respondents surveyed (47 per cent) allowed their children to travel in the front seat between the ages of seven and 12. The hospital says that children in the front seat are twice as likely to be injured in a crash.

While the law allows children as young as four to sit in the front, it's only in certain specific circumstances. If every other seat in the vehicle – apart from the driver's, of course – is occupied by a child under the age of seven, a four-year old may occupy the front seat.

Legally, children aged seven or higher may occupy the front seat without restriction, but the RCH recommends strongly against that.

Two thirds of respondents (63 per cent) had placed their child in a forward-facing seat before the child was 18 months old.

Of the respondents polled, almost without exception they complied with the law. In fact, 95 per cent of parents were meeting legal requirements for their children between the ages of two and four years. The legal compliance rate for children aged between four and seven years was higher still, at 98 per cent. And all the parents taking part in the survey complied with the law for their kids up to the age of two and between the ages of seven and 11.

However, while the parents surveyed unanimously followed best practice for their children up to the age of six months, few continued to apply those principles – in line with the hospital's recommendations – between six months and two years or between seven and 11.

• Keep your baby in a rear-facing capsule until the age of two, unless the child outgrows the capsule,
• Use a forward-facing seat up to the age of four at least (mandated by law), but preferably longer if the child has not outgrown the seat by that age,
• Transition to a booster seat from no earlier than four until the child has reached 145cm in height,
• Once the child has reached the minimum height of 145cm, assess whether the child passes the 'five-step' test,
• If the child is 145cm tall or can pass the five-step test, they need not use a booster seat,
• Although the law allows it, children under the age of 12 should not sit in the front seat, the RCH Advises.

Your child may not be 145cm tall, but may sit comfortably in the back of a Porsche 911 (as an example) if he or she can pass the 'five-step' test, which is as follows:

• Can the child sit comfortably with his or her back resting against the seat squab?
• Can the child do so with his or her feet resting flat on the floor (with knees bent over the leading edge of the seat base)?
• Does the sash belt cross the child's body at the mid-shoulder region?
• Is the lap belt positioned comfortably across the top of the thighs?
• Lastly, can the child comfortably maintain that seating position for the duration of the journey?