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Need One? Yes!!
Experienced, careful bike riders crash every 4,500 miles on the average. Head injury causes 75% of our 800+ annual deaths from bicycle crashes. Medical research shows that a bicycle helmet can prevent 85% of cyclists' head injuries. And helmets may be required by law in your area.
How Does a Bicycle Helmet Work?
A helmet reduces the peak energy of a sharp impact. This requires a layer of stiff foam to cushion the blow by crushing. Most bicycle helmets do this with expanded polystyrene (EPS), the white picnic cooler foam. Once crushed, EPS does not recover. Another foam, expanded polypropylene (EPP), does recover, but is much less common. A stronger EPS called GECET appeared in 1992 and is widely used now. Another foam called EPU (expanded polyurethane) is used in Taiwan. It has a uniform cell structure and crushes without rebound, but is heavier and requires a manufacturing process that is not environmentally friendly. The spongy foam inside a helmet is for comfort and fit, not for impact.
The helmet must stay on your head even when you hit more than once--usually a car first, and then the road. So it needs a strong strap and an equally strong fastener. The helmet should sit level on your head and cover as much as possible. Above all, with the strap fastened you should not be able to get the helmet off your head by any combination of pulling or twisting. If it comes off or slips enough to leave large areas of your head unprotected, adjust the straps again or try another helmet. Keep the strap comfortably snug when riding.
What Type Do I Need?
Most helmets are made of EPS foam with a thin plastic outer shell. The shell helps the helmet skid easily on rough pavement to avoid jerking your neck. The shell also holds the EPS together after the first impact. Some excellent helmets are made by molding EPS in the shell rather than adding the shell later.
Beware of gimmicks. You want a smoothly rounded outer shell, with no sharp ribs or snag points. Excessive vents mean less area contacting your head, which could concentrate force on one point. "Aero" helmets are not noticeably faster, and in a crash the "tail" could snag or knock the helmet aside. Skinny straps are less comfortable. Dark helmets are hard for motorists to see. Rigid visors can snag or shatter in a fall. Helmet standards do not address these problems--it's up to you!
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Standards
A sticker inside the helmet tells what standard it meets. Helmets made for U.S. sale after 1999 must meet the US Consumer Product Safety Commission standard, so look for a CPSC sticker. ASTM's standard is comparable. Snell's B-95 and N-94 standards are tougher but seldom used. The weak ANSI Z90.4 standard is dead. Fit is not certified by any standard, so test that on your own head. Visors are not tested for shattering or snagging in a fall, so you are on your own there.
Comfort
Coolness, ventilation, fit and sweat control are the most critical comfort needs. Air flow over the head determines coolness, and larger front vents provide better air flow. Most current helmets have adequate cooling for most riders. Sweat control can require a brow pad or separate sweatband. A snug fit with no pressure points ensures comfort and correct position on the head when you crash. Weight is not an issue with today's helmets.
Special Problems
Ponytail ports can improve fit for those with long hair. Bald riders avoid helmets with big top vents to prevent funny tan lines. Some head shapes require more fiddling with fitting pads and straps. Extra small heads may need thick fitting pads. Extra large heads up to 8 1/4, may require the huge Bell Kinghead. For a softer landing, seniors should pick a thicker, less dense model without huge vents.
Special Problems
Ponytail ports can improve fit for those with long hair. Bald riders avoid helmets with big top vents to prevent funny tan lines. Some head shapes require more fiddling with fitting pads and straps. Extra small heads may need thick fitting pads. Extra large heads up to 8 1/4, may require the huge Bell Kinghead. For a softer landing, seniors should pick a thicker, less dense model without huge vents.
How to Buy
When you pick up a helmet, look first for a CPSC sticker inside and a smooth shell with a bright color outside. Put it on, adjust the pads and straps or the one-size-fits-all head ring, and then try hard to tear it off. Look for vents and sweat control. Helmets sell in bike shops or by mail order from $20 up, or in discount stores for less.
A good shop helps with fitting, and fit is important for safety. A discount helmet can be equally protective if you take the time to fit it carefully. Helmets are cheap now, so don't wait for a sale. Many of us bought our helmets after a crash. You can be
smarter then that! |
When to Replace a Helmet?
Replace any helmet if you crash. Impact crushes some of the foam, although the damage may not be visible. Helmets work so well that you need to examine them for marks or dents to know if you hit. Most manufacturers recommend replacement after five years. We think that depends on usage, and most helmets given reasonable care are good for longer than that. But if your helmet is from the 70's, it's time to replace it. Replace the buckle if it cracks or a piece breaks off. No one requires you to replace your helmet, so give it some individual thought.
Bike Helmets for Skating?
The ASTM standards for biking and inline skating are identical. But aggressive skating and skateboard helmets have their own ASTM standard, designed for multiple hits with lesser impact severity. Do not use a skate helmet for bicycling unless it has a CPSC sticker!
Consumer Reports Article
Warning: Children must remove helmets before
climbing on playground equipment or trees,
where a helmet can snag and choke them.
Consumer Reports published a helmet article in 1999 with brand recommendations, but the helmets no longer sold. If they have published a new article by the time you read this, you can find it at your local library or download it from www.consumerreports.org for a fee.
Bicycle Helmet Safety Institute
4611 Seventh Street South
Arlington, VA 22204-1419 USA
(703) 486-0100 info@helmets.org www.helmets.org
We are volunteers, all funded by consumers like you.
©BHSI, 2002. OK to reproduce for non-profit use. |
