A helmet sold as a bicycle helmet in the United States must meet CPSC bike safety standards. Most helmets certified for bicycle use have an inner liner made of expanded polystyrene (EPS). This is a stiff foam designed to absorb the impact of a single big hit. In the event of a major collision, a single-impact helmet will probably absorb the hit better than a soft-foam helmet. The trade-off is that the EPS foam liner is not designed to absorb multiple small hits. While the term "bike helmet" may conjure up images of skinny, aerodynamic designs with a ton of vents, a number of manufacturers make CPSC-certified helmets with the rounded, bucket shape of a traditional skate helmet. Many helmet manufacturers also make what we call “bike/skate helmets.” Bike/skate helmets have the styling of a skateboard helmet but with a liner you’d more often associate with a bicycle helmet and meet CPSC safety standards.
A multi-impact helmet is generally styled like a skateboarding helmet and has a soft foam liner to help cushion the impact of multiple small hits. Skate helmets don’t have the aerodynamic design that you see on a standard bicycle helmet. They’re rounder and have a longer side and back to protect more of the back of your head and neck. At XSportsProtective, we typically call these “skate-only” helmets because they do not carry a CPSC bicycle helmet certification. Some “skate only” helmets meet ASTM safety standards for skateboarding and trick skateboarding (yep, that’s what they call it. Trick skateboarding.) Some do not. A lack of ASTM certification does not make a helmet unsafe. It simply means that the manufacturer chose not to pursue the extra cost of certification. Many of our customers prefer to use skate helmets for roller derby because the liner is soft and comfortable and, in some cases, removable for easy cleaning.
Roller derby helmets are usually sold in one of three exterior shell sizes (small, medium, large) along with sometimes interchangeable fit pads to customize the fit and snugness. Every helmet has a sizing table in its description that shows the head size (usually in centimeters for more accuracy) and corresponding helmet size (Small, Medium, Large, etc.). The first step in determining what size roller derby helmet you need is measuring your head with our Helmet Sizing Guide.
The way a helmet rests on your head is critical to how it will perform for its intended use. Proper helmet fit means proper head coverage. When you try on a helmet, the front of the helmet should sit down onto your forehead until just above your eyebrows. There should be room enough to slip on a pair of sunglasses, but not much more. A half-inch in most cases. The helmet should not move when you shake your head, but it should not be so snug that it hurts/leaves a mark on your forehead.
Different manufacturers make different helmet molds. What’s important for you as the wearer is that the helmet fits comfortably all the way around your head. If you think you’ve got the proper size, but the helmet is still a little roomy in a spot or two, that is not a big deal. You can add included fit pads where necessary to achieve a more secure fit. However, if you’ve selected what you believe is the proper size, but feel an uncomfortable pressure anywhere around the circumference of your head, then the helmet is probably too small for you. Try a different size or style of helmet from the same line or try a different manufacturer altogether. To find a helmet that fits you comfortably, start with XSportsProtective’s Helmet Sizing Guide, then use your head measurements to compare all of the different helmet offerings from the different manufacturers that appeal to you. Most likely, you will find a good selection to choose from.