Merck Manual

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Bike Helmet Safety
Bike Helmet Safety
Bike Helmet Safety

    Bicycle riding is about as safe as walking. But when you’re riding in traffic or down a mountain trail, it can be dangerous. Wearing a safe bicycle helmet correctly is the best way to protect your head in a crash.

    Helmets have changed over the years, and there are helmets made for lots of different activities. Some are multipurpose, but they may not be made for riding. Start by picking one that’s certified for biking.

    To choose a helmet, first find the circumference of your head where a hatband or sweatband might sit. Use a fabric tape measure or piece of string and measure it with a ruler.

    Next, make sure the helmet’s not on backwards. Hey, it happens! Turn the dial to adjust the tension until it's snug — nod and shake your head. The helmet should stay in place.

    Adjust the helmet so that the front edge is level across your forehead, and 1 or 2 fingerbreadths above your eyebrows. So it protects your head and face.

    Next up, the chinstrap should be snug enough to allow only 1 or 2 fingers between the strap and your chin. If you feel a bit of tension when you yawn, you’ve done it right.

    Next, slide the side adjusters up so the side straps form a “V” with the point RIGHT under your earlobes, and ensure that both sides of the V are nice and taut. Straps often loosen — so check them when you put your helmet on and re-tighten as needed.

    Finally, look in a mirror to check your work — and make sure you look great! Things can jiggle a bit as you ride, so you may need to adjust a bit along the way.

    Finally, remember that for most helmets, once you've crashed, the helmet is trash, and it's time to get a new one.

    Alright, as a quick recap:

    • Select a helmet that is safe for biking and fits your head.

    • To wear it correctly make sure the helmet is level and just above your eyebrows.

    • Then, adjust the tension knob and straps so they hold the helmet properly in place.

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