Safety first!
A helmet that is too big or too small is a safety hazard. Wearing a suitable helmet can reduce the risk of serious injury should you have an accident while riding your bicycle.
Adults should always attach the straps when wearing a bicycle helmet as a good example for their children. Protection from an injury is also very important for the parents.
Children today are making better decisions regarding their safety when playing outdoors. There are numerous visual examples available for kids to model, from community sponsored safety events to television shows geared to promote safe practices.
A bicycle helmet will reduce the energy that your head will bear if you fall and crash. Foam in the helmet is used to cushion the blow. Most bicycle helmets contain expanded polystyrene (EPS), the same foam found in white picnic coolers. Stronger foam called GECET was introduced in the early 1990s which is widely used now.
The helmet must stay on your head. You may get hit more than once in an accident. A car may hit you, and then you may fall or get thrown on the road. So the bicycle helmet should have a strong strap and fastener. The helmet should sit level on your head, and with the strap fastened, you should not be able to pull it off.
You may need to try on different bicycle helmets until you find one that offers both, comfort and safety.