Booster Seats and the Five Step Test


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Safety belts are designed to fit the average adult male. Women and children (especially in older vehicles) simply do not fit. While there is little that can be done for adults (we’re still working on boosters to fit grown-ups who might want them LOL) belt positioning boosters make that adult belt fit your child.

Keep children in booster seats until they pass the "5 Step Test" (usually around 10-12 years old and close to 5 feet tall) in every vehicle in which the child rides. If the child meets the 5 Step Test in one vehicle, but not another, the child will need a booster for every vehicle in which the 5 Step Test is not met.

Weight is a useless measurement of whether a child is ready for the adult seat belt or not. Age is only helpful when considering the child's ability to sit properly.

In order to work properly, a shoulder belt needs to be across the collarbone and the lap belt needs to be on the hipbones. However, children often slip the shoulder belt under their arm or behind their back, losing all upper-body protection. Or, they slide forward so their knees bend comfortably over the edge of the seat, making the lap belt ride up on the abdomen. In these cases, the seat belt CANNOT work properly! Children can slide down and out of the restraint, or the belt can be forced into the stomach, causing damage to internal organs. These types of injuries are known as "seat-belt syndrome."

However, some children should NOT be in boosters.
Children under 40 pounds and under the age of four should remain in a 5 point harness at all times.

A booster does not restrain the child the way the harness does, it simply "boosts" the child up in order to make the adult-sized belt safely fit a child-sized body. Children under age 4 do not possess the ability to sit perfectly at all times, and a child who leans forward to retrieve a cup or toy, or who twists around to see something or someone behind them, will not be protected in a crash and is at risk for serious injuries and possibly death. Also, children this age sometimes still fall asleep in the car. The slumping that occurs when this happens means they are not properly positioned and should be in a 5 point harness for that trip. Ideally all children should remain in an appropriate 5 point harness until age 5.

The 5 Step Test
If you answer "No" to any of these questions, your child must be in a booster seat:
1. Does the child sit all the way back against the auto seat?
2. Do the child's knees bend comfortably at the edge of the auto seat?
3. Is the lap belt touching the top of the thighs, not the tummy?
4. Is the shoulder belt centered on the shoulder and chest?
5. Can the child stay seated like this for the whole trip?

BELT-POSITIONING BOOSTERS CAN NOT be used with only a lap belt!
(See your car dealer for a lap/shoulder belt retrofit.)

So what booster is best for your child?
That is a complex question with no hard and fast answers. The best booster for your child is the one that fits your child, your vehicle, your budget and that you will use correctly each and every time. Some boosters (like other car seats) are outgrown early by height, others can be tricky to use properly. Others are very expensive.

DO NOT use a shield booster. These are VERY dangerous and should never be used. For more information, see:
Shield Boosters provide little or no upper-body protection. In many cases, the children who are injured or killed in these either:
Get flung too far forward, resulting in serious head or spinal injuries or
Submarine UNDER the shield and have spinal/neck injuries or are actually decapitated.
There are also unfortunate cases where children are thrown OUT in a side-impact or rollover collision.

For children under age 4, and under 40 pounds, use a "COMBINATION BOOSTER". This is a seat which has an integrated five-point harness which can be removed once the child outgrows it, and the seat can then be used as a belt-positioning booster at that time. This will NOT be the last seat your child needs, as the current models are typically outgrown by height (tips of ears above the shell of the seat) well before the 5 Step Test (above) is passed. However, at that point in time, if your vehicle has high seat backs or adjustable head restraints (aka "head rests"), an inexpensive backless booster may be an option for you.
Once you move your child to a belt-positioning booster, leave them there until they pass the 5 Step Test - no matter how old they are or how much they weigh. This may mean purchasing more than one booster, and it may mean having your 8, 10, or 12 year old in a booster!!!
If your child is OVER 4 years and 40 lbs, and sits properly for every ride, every time, a booster is acceptable, although a 5 point harness is still much safer AS LONG AS the child has not outgrown the seat.

Some boosters are shorter than others, some are wider. Some fit well in small seats, others do not fit well in conjunction with other child restraints. Be aware that should you choose a shorter booster, you may need to purchase another booster later because your child outgrows it by height.

Boosters are outgrown by height when the shoulders are above the belt guide at it's tallest setting OR the ears are above the shell of the seat. They are outgrown by weight when your child meets the weight limited listed on your seat and in the manual for the seat.

Some boosters function as both high back boosters and "BACKLESS BOOSTERS". If you choose a booster with this configuration, and the booster is outgrown by height as a high-back booster, some manufacturers permit you to remove the back and use the booster as a backless as long as proper head support is available in your vehicle. Before attempting this with your booster, verify that the manufacturer allows this by reading your owners manual.

Whichever type of booster you purchase, whichever brand you buy, use it every ride and every time. Don't prematurely evict your child from the booster. Explain to them in as much detail as necessary why they must use a booster, even if their friends do not.
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