Choosing the Right Helmet

October 27, 2004

Head First: A primer on helmets

An ice climber in Franconia Notch, NH. Photo: AMC Files

AMC Outdoors, November 2004

I feel a strong personal connection to my helmets. A few years ago, I crashed on my road bike (over an unleashed dog) at about 20 miles per hour. The impact bent my bike frame and cracked my helmet, but instead of sustaining a possibly permanent head injury, I walked away from the accident. On two unfortunate occasions, I’ve witnessed the effects of a high-speed collision between a rock and a human skull, and it’s not a picture I’d care to describe here. These days, I not only don a helmet whenever I climb or bike, I get a sick feeling every time I see an adult or child without one in any sport that should demand head protection.

The statistics strongly suggest that my reaction isn’t merely emotional. The Bicycle Helmet Safety Institute ( reports that 540,000 bicycle riders in the United States visit emergency rooms every year, approximately 67,000 with head injuries. Two-thirds of the 800 cycling deaths that occur annually are from traumatic brain injury. Tragically, half of those deaths are children under 15. Helmets could prevent up to 88 percent of brain injuries, yet only about 25 percent of the 85 million American bicyclists wear them.

For climbers, head injury is the third-leading cause of fatalities, according to Jed Williamson, U.S. editor of the annual report Accidents in North American Mountaineering. Rocks, ice, or other objects falling from above (like gear dropped by climbers) are usually the greatest hazards, though not the only ones. Longtime climber John Harlin III, editor of The American Alpine Journal, once received 17 stitches in his head after falling while not wearing a helmet. “I think [helmet use] should become standard in climbing,” he comments. “One should be considered uncool for not wearing a helmet.”

Ski resort visitors should also take note—the U.S. Consumer Products Safety Commission estimates that 7,700 skiing and snowboarding head injuries and 11 deaths could be prevented every year by increased helmet use. Recent studies show that appropriate protection could prevent or reduce the severity of 44 percent of head injuries sustained by adult skiers and snowboarders, and 53 percent of those suffered by children under 15.

In fact, all outdoor sports that involve speed and agility require head protection. In addition to bicycling, skiing, and all forms of climbing, helmets should be worn while inline skating, riding a scooter, skateboarding, or whitewater or surf boating (where you can be thrown from the boat or tumbled upside down in rocky or shallow water).

Safety on the mind

By law, all helmets sold in the U.S. must meet standards set by the Consumer Products Safety Commission. Helmets for outdoor sports should also meet the performance standards of the American Society for Testing and Materials (ASTM) or the non-profit Snell Memorial Foundation ( ASTM evaluates helmets using tests that cover everything from the strength of a helmet’s retention system under simulated hot, cold, and wet conditions, to the effects of multiple impacts and velocity forces on various parts of a helmet.

Fit is critical with any helmet. Before you buy, try out different models—place them straight down on the crown of your head, with the front brim straight across your forehead (tilting a helmet backward leaves your forehead unprotected). A properly fitting helmet will cover your head comfortably without any gaps on the sides or in back. Once adjusted, it should not shift side to side or front to back, even before buckling the chinstrap. If your sport’s helmets come in multiple sizes, use a cloth tape measure to determine the circumference of your head where it’s largest, about an inch above your eyebrows. If you’re between sizes, get the smaller one as long as it’s comfortable.

Once you’ve determined the correct size, properly adjusted it, and buckled the chinstrap, the helmet should press down on your forehead when you open your mouth; if it doesn’t, tighten it. Helmets vary in weight—a difference of ounces is noticeable, particularly on longer outings. You’ll pay more for a lighter helmet, and the price also tends to increase with the amount of air vents, good for hot-season sports. For a cold-weather sport like ice climbing, fit the helmet to allow a balaclava or other thin insulating layer underneath.

Sport-specific helmets

Helmets are designed differently depending on the sport, and provide coverage for the type of impacts likely to be encountered in that specific activity. For example, cycling helmets are not designed to withstand a heavy impact on the top or back like climbing helmets.

Bike helmets almost always consist of a polyethylene plastic shell over a foam insert. The smooth plastic helps the helmet slide on impact, which protects your head and neck, and works in collaboration with the foam to absorb and dissipate the force of a collision. A helmet may crack in an accident, proof that it took the shock rather than your head.

Cycling helmets come in three basic styles: sport, road, and mountain bike. All are designed to protect riders from impact, but vary slightly. Sport helmets are less expensive and used by commuters, road and mountain bikers, and inline skaters. Road biking helmets are lighter, well ventilated, and aerodynamic. Mountain bike helmets—also used by cyclocross riders—offer maximum protection from trailside obstacles, provide extended coverage over the back of the head, and usually have visors. Some helmets are designed for both road and trail riding. Bike helmets come in several sizes and can be precision-fitted using pads and adjustable straps.

Most climbing helmets are composed of plastic shells with both an internal webbing suspension and a polystyrene foam liner. The webbing not only dissipates impact force, it can be adjusted to fit variable head sizes and permits ventilation between the shell and your head, a nice attribute on steamy ascents. Another important feature to look for is attachments to hold headlamp straps, critical for helmeted night-time activity.

Newer climbing helmets protect against side impacts better than older styles, though they should all meet international standards set by the European Committee for Standardization (CEN) and Union Internationale des Associations d’Alpinisme (UIAA). Most are adjustable one-size-fits-all styles, though some models are available in more than one size. If you have trouble finding a good fit, shop around.

Skiing and snowboarding helmets typically consist of an injection-molded high-density plastic (ABS) shell designed for heavy impacts, and often weigh more compared to other helmets. Manufacturers have strived to make them lighter, though some argue that heavier hard-shell helmets offer the most protection. They often come equipped with removable earflaps for extra warmth, an adjustable padded chinstrap, and usually feature little ventilation—skiing being a cold-weather sport. Look for helmets that provide secure attachments for goggles and do not impede peripheral vision. Some models offer an integrated chin bar for facial protection, meant for people who ski or snowboard fast or like to perform snow park tricks.

Helmets for whitewater and surf boaters are usually made of an ABS shell with a closed-cell foam lining, and feature vents to allow air and water flow. They are getting more varied in style, and today’s models range from the traditional motorcycle-style helmet with ear coverage to beanie-style “competition” brain buckets that sit entirely above the ears. Some specialized models, used mostly by play boaters doing whitewater tricks, have a face mask.

Some boating helmets come in one adjustable size, while others are available in multiple sizes based on head circumference in inches. Whatever the style, basic fit remains the same as other helmets—make sure it’s comfortable and fastens securely under the chin. For the oft-chilly rivers and surf of the Northeast, make sure your helmet fits over a warm head layer.

Don’t let your over-confidence go to your head, no matter how good you are at your chosen outdoor pursuit—wear a helmet!

An archive of Michael Lanza’s columns can be found at toolstrappings/.

Search AMC Outdoors and Blogs

Search for:

Michael Lanza

AMC Outdoors, the magazine of the Appalachian Mountain Club, inspires readers to get outside and get engaged. Learn more.