Book 3, Question 113
Why Do Helmets Have Foam?
A helmet is a crash sandwich. A hard shell spreads out a hit, and thick foam crushes on purpose, so your head slows down more gently. Sudden stops hurt.
From the book
Page from A Million Whys Book 3
More fun facts
- A standard bike helmet with foam padding can absorb about 88 percent of the energy of a hit.
- Absorbing that energy means less of it reaches your head.
- In bike crashes, riders hit their heads about 38 percent of the time, and for children the rate is even higher, at 55 percent.
- A 16-year-old student in Canada invented a gel liner for helmets that squishes to soak up energy and spread it out.
- Her tests suggested a helmet with the liner could protect the head from about 97 percent of an impact's energy.
- A review found that, when worn correctly, bike helmets help reduce the risk of head injury.
Sources: Science News Explores, BBC
Questions kids ask
What does the foam in a helmet do?
It squishes on impact and soaks up energy, so less of the hit reaches your head.