Summary: Helmet users sometimes are annoyed that it seems they need a different helmet for every sport. In many cases you do, but in a few others you can find a multipurpose helmet.
We specialize in bicycle helmets, but we are involved in standards-setting for others as well. We have a page up on Other Helmets that you might want to check for comments on helmets for your own activity. Here are some comments on using helmets for different sports.
Why not just one helmet?
Even the best helmets are not able to protect against every blow. For maximum protection they have to be optimized for the type of blow you expect. Some sports have sharp impacts against pavement, which has zero give. The energy spike is very sharp and short. Other sports are played on turf or something with a little bit of give. That makes an enormous difference in the helmet you need.
Some sports have unique problems. Equestrian helmets have to withstand the sharp edge of a horse's hoof. Whitewater helmets have to deal with "bucketing" in very fast water flows and drain well. Hockey helmets need facial protection. Football helmets are designed for thousands of blows per season. Auto racing helmets must be fire-resistant. The list goes on, and you can probably add an example from personal experience.
In some sports, crashes are not frequent and the helmet can be discarded when a big impact occurs. Others involve constant falling and many many smaller impacts. For these sports a one-use helmet would be a nuisance, and probably would not be replaced when it should be. So some compromises are normally made in protection to make the helmet multi-impact.
Two basic types of helmets
Helmets are usually in two categories: one-use and multi-hit.
Single use helmets are mostly made with expanded polystyrene (EPS) because it is cheap, light, easy to manufacture and has excellent crush characteristics with very little rebound. Once crushed it recovers some part of its thickness, but does not recover its protection. If you don't discard it after the first hit, you will be in for a nasty surprise if you happen to hit on the same spot for a second hard impact! Bicycle, motorcycle, roller skate and equestrian helmets normally use EPS for impact energy management.
The first multi-use bicycle helmets were made with expanded polypropylene (EPP). EPP looks like EPS, but has a slightly rubbery feel. It recovers slowly after a blow and is good for more hits. Nobody can tell you how many more hits, but some. Its crush and manufacturing characteristics are not quite as good as EPS, so the helmet might have to be thicker, and it rebounds enough during the impact sequence to make it less than ideal, although the rebound occurs after the lab has measured the performance of the helmet and is missed in standards testing. EPP is used extensively in automotive padding, for things like the foam to back up a bumper. There are now on the market a few EPP helmets that meet both the CPSC bicycle helmet standard and the ASTM F1492 skateboard helmet standard. They have stickers inside telling you that. We list them on our page on dual-certified helmets.
Multi-hit helmets are mostly made with butyl nitrate foam, a "squishy" but dense foam that is good for many impacts. It is mostly black or gray. It is heavier than EPS and cannot manage as much impact energy for a given thickness. Hockey and football helmets are made this way, and so are whitewater, old-style skateboard and aggressive trick skating helmets. You don't have to throw the helmet away after a hit, but it normally is not much thicker than an EPS helmet, and that means it will not manage as big an impact. Typical lab drops for multi-use helmets are one meter. For single-use EPS helmets the typical drop is two meters. That's a very large difference in impact protection.
Another "squishy" foam, but with superior impact characteristics is the foam marketed by W Helmets as Zorbium. Behind the glitzy name is a really good foam, good for multi hits and "rate-sensitive" to make it stiffen up if the impact is really hard and ease up if the impact is lesser. It might be a good choice if avoiding concussions is your primary goal. (Most helmets are designed to protect primarily against the high-end impacts that cause catastrophic brain injury, letting enough energy through to give you mild concussions.) Zorbium helmets from W Helmets are hot, heavy and soak up sweat, but some of them meet bike, ski and skateboard standards.
Which helmets are interchangeable?
Usually you should not use a single use helmet for a multi-hit sport because it will not be replaced when it should be (after one hit) and when you hit again there will not be enough protection left. Looking at a crashed EPS helmet will make a believer out of you. And you should not use many of the multi-impact helmets for single-hit sports like bicycle riding because they will not have enough protection in that big hit. So you might use a skateboard helmet for another sport where the impacts are similar, (repeated, less severe) but you would not use one for equestrian events. Roller skaters are in luck: their activity is now included by ASTM in its bike helmet standard, which is identical to the CPSC bicycle helmet standard.
There are a few one-hit helmets made of EPP, Zorbium or another recovering foam that can be used for more than one type of sport. If you find a bike helmet with EPP or Zorbium it should be fine for skateboarding, for example. Consumer Reports in their July 2002 article found one Pro Tec skate helmet that meets the CPSC bicycle standard, and Pro Tec has additional models in their 2004 line. The other skate helmets Consumer Reports tested did not meet the bicycle standard. We are not aware of any other crossover helmets using squishy butyl nitrate foam. Do not assume that if you buy a "skate style" helmet that it is designed for skateboarding! When we checked the big box retailers in our area the helmets we find are usually bicycle helmets certified to the CPSC bicycle helmet standard, all single-hit EPS helmets. But there are now some helmets certified to both bicycle and skateboard standards. We have a list of dual-certified helmets up, and a separate page on skate vs. bicycle helmets.
The definitive way to see what a helmet will protect for is to look for the stickers inside that tell you what standards it meets. A bike helmet must meet the CPSC standard, by law. But the law applies only to bicycle helmets. There is a skateboard helmet standard, ASTM F-1492, but no law requires manufacturers to use it, and most consumers don't even know enough to look for the sticker. Only specialized stores carry skateboard helmets, and some of those do not meet ASTM F-1492. The big retailers are selling bicycle helmets with the skate shape. The ideal multi-purpose helmet would have at least two stickers in it, or one sticker that says it meets the two activities you want to use it for.
The Snell Memorial Foundation has a multi-purpose standard, called Snell N-94. There is a list of certified helmets on the Snell Web site. Snell believes that based on their testing of those helmets they offer adequate protection for "non-motorized activities" but their description of the standard limits that to bicycling, roller skating and skateboarding.
The Government to the Rescue!
The Consumer Product Safety Commission has worked on this subject and produced a really informative pamphlet called "Which Helmet for Which Activity" that has a chart showing their recommendations. You can find it on their Web site. We recommend it highly.
In short you will have to be very careful to find what you are looking for. Helmet requirements vary for different activities, and although the technology has advanced enough to combine multi and single hit helmets, you won't get one unless you look carefully. In the past, manufacturers typically did not go out of their way to inform you that a helmet was good for multiple activities. That increases their legal liability and might cut into their sales. And the differences in helmets are significant enough to make it difficult to manufacture a helmet that is really versatile without compromises you probably do not want to make. But the current demand for multi-purpose helmets has led some to add skateboarding to the outside box decals, even if the helmet is not certified to the ASTM skateboard standard, and even if it is not designed for multiple hits. In effect, real human subjects in the field are now testing whether or not skateboarders really need multiple hit helmets. You don't want to do that, so look carefully at the certification stickers to be sure the helmet is certified for the sport(s) you want to use it for.
The amount of protection you are willing to settle for is, of course, your own personal decision in areas that don't have helmet laws. If you wear a skateboard helmet for bicycle riding that does not have the CPSC bicycle standard sticker inside you might think it's better than nothing, but you should know that a significant percentage of the head impacts will be more than that helmet can take and keep your brain in one piece. When a CPSC helmet is only about $20 at a discount store, and Consumer Reports is finding that cheaper helmets are more protective anyway, why risk it? Or if you send your child out in a bike helmet to do some halfpipe skating or snowboarding where falls are constant, you will have no way of knowing when the child returns whether that helmet they will wear again next time had an impact that ruined it or not. The child will not know, since helmets cushion the blow, or will just forget to tell you. Although this advice is annoying, a different helmet may be the only way to have maximum protection. Helmets don't work every time anyway, and compromising by using a helmet not designed for the activity is stacking the deck against the user.
If you run across any true multi-purpose helmets that we don't know about in our annual writeup or our dual certified helmet page, please drop us an email!
This page was last revised on: February 13, 2007.