It's the law in every state that infants and children must ride buckled up, either in a car seat or using seat belts. Even so, more children in the U-S are killed or injured from car crashes than from any other type of injury. Many of these deaths and injuries could be prevented if the safety seat or seat belt had been used correctly. There's not one brand that everyone agrees is the safest or best. The 'best' is one that fits the child's size and weight, fits your car, and will be used correctly each time. You should keep a child in a convertible or booster seat for as long as possible, and make sure the child is facing the right way for both weight and age. When the child's outgrown seats, be sure a seat belt fits correctly. Sitting in the back seat is safer than the front, and a lap and shoulder belt is better than just a lap belt. Safety precautions also are important when a child rides a bicycle. The child should wear a helmet, which reduces the risk of head injury by 85 percent. Laws vary from state to state, but most states and municipalities require children to wear a helmet. The American National Standards Institute and the Snell Memorial Foundation set standards for helmets. Look for their sticker. You can start children wearing a helmet even when they're still in the tricycle or training-wheels stage. Make sure the child is with you when you buy the helmet to ensure that it fits properly. Don't buy one a little big so the child will grow into it; it should fit properly immediately. The helmet shouldn't be too tight, and it should cover the top of the forehead. Of course, adults should wear helmets, as well, both for their own protection and to set a good example.