My cycling buddy Mandy has justly earned the nickname “helmet Nazi.” Whenever she sees someone riding without a helmet, whether it’s a child or adult, acquaintance or stranger, she’s likely to give them a lecture about the necessity of wearing helmets. As she says, you can’t live without your brain, so don’t be stupid and leave it unprotected.

People have many excuses for not wearing helmets: they’re not cool; it’s too much trouble; they’re too hot; I don’t want helmet hair; and so on. I’m guessing that for you, as for me, the possibility of suffering brain damage (or death) due to a fall off a bike is also not cool and is definitely way too much trouble. As far as being too hot, modern helmets are so light and designed with so many vents that your head will stay nice and cool. And if your hair is your biggest concern, buy a brush.

The thing to remember is that it’s not your riding skills that are in questions; it’s the unpredictability of other riders or automobile drivers, the debris on the trail, the dog that comes after you out of nowhere, and any number of other factors that can cause you to lose control of your bike. You can’t control the world around you, so do what you can to protect yourself from dangers seen and unseen.

It’s not just important to wear your helmet every time you ride, but also to wear it properly. It must fit you well and must be sitting on your head correctly. You may also need to replace your helmet periodically.

How Your Helmet Should Fit
Helmets come in different sizes, so be sure to get the right size. There are helmets for infants and children, women’s sizes for smaller adult heads, and a more “standard” adult size. Most sizes and styles have a range of adjustability that allows you to ensure it fits perfectly. Some also have additional pads to help you dial in the fit. Try on sizes and styles until you find the right one for you.

When adjusted correctly, your helmet should fit snugly, but not tight. With the chin strap fastened (and you should always fasten it or it will just fall off) you should be able to just slip two fingers between the strap and your chin. Put your hand on top of your helmet and wiggle it a bit. It should just move slightly, but not be sloppy on your head. It shouldn’t be so tight that it’s uncomfortable, but also not so loose that it slides around on your head.

How to Wear Your Helmet
Once you have your helmet properly adjusted for size, make sure you always put it on properly. It should sit straight on your head, not tipped to the back. Most new helmets come with visors to help keep the sun out of your eyes, a function they can only perform if the visor sticks straight out from your forehead. Additionally, the helmet won’t provide full protection if it’s not seated properly on your head.

When to Replace Your Helmet
Modern bike helmets are primarily made of plastic and Styrofoam, both products which will lose strength and integrity over time and with exposure to UV light from the sun. If any of these conditions is true, replace your helmet:

1. It doesn’t fit properly.
2. You’ve crashed while wearing it.
3. It’s been dropped hard enough to crack the plastic.
4. The straps are broken or worn.
5. It was manufactured during the 1970s or early 80s (it probably won’t meet current safety standards).
6. It doesn’t have an ASTM or Snell sticker. These organizations have the accepted standards for testing bike helmets; most modern helmets meet these standards and say so.
7. You just don’t like wearing it. If you don’t like your helmet, you’re more likely to find excuses for not wearing it.

Regularly inspect your helmet for signs of wear: abrasions, small cracks, soft spots, worn liners or straps, etc. Signs of damage, especially cracks and soft spots, are indications that your helmet needs to be replaced.

When to Wear Your Helmet
In a word: Always! Just because you’re a grownup doesn’t mean you’ve outgrown the need for a helmet. You’ll not only protect yourself, but set a good example for the next generation of cyclists. If you go on an organized tour or group ride, helmets will be mandatory, so you might as well get used to it. Just wear it!

Ride safe and have fun!