Helmet Tech in Snow Sports

Helmet Tech in Snow Sports

Leif Edwardson, DC, MSc Sports Medicine

There is no question that if you are out skiing or snowboarding this winter, you should be wearing a helmet. Helmets are crucial in helping prevent some traumatic brain injuries, and should be worn by every rider out on the slopes. Although helmets do not prevent concussions, they can reduce risk for them and serious traumatic brain injuries, as well as protect against puncture wounds and skull fractures. Helmet technology has changed a lot over the last 10 years, and it can be confusing to understand the different systems and materials to buy the best and safest helmet for you. 

This blog will cover what is important to look for in a helmet, and some of the commonly available helmet technology that is available at this time. If you want a quick summary, scroll down to “My Recommendation”, although I encourage you to read the whole article if you have time. Covered in more depth below:

Helmet Fit

Basic Safety Standards

Rotation Damping Systems

• MIPS
• WaveCel

When to Replace a Helmet

My Recommendation 

Helmet Fit:

Possibly the most important aspect of a helmet is fit. If a helmet is not fitted properly, it can’t do its job and could even come off in a big crash. The ideal helmet is the smallest size shell that is comfortable on the head. It should not shift around when shaking your head back and forth. Helmets are designed to fit a generic shaped head, so it is important to try them on— find one that fits and is comfortable to you. Remember that chin straps should be tight enough that they can’t slip over the chin, but loose enough to not choke you. 

Basic Standards: 

Standardized helmet testing has some major flaws, but will likely continue to evolve and incorporate new elements as our technology and knowledge improves. The ASTM F2040 certification is important because currently it is a baseline that shows there is some level of safety testing for the helmet to pass. The American Society of Testing and Materials has a standard test and certification designed for non-motorized snow sport helmets (F2040), as well as separate certifications for climbing, biking, and motorized sports helmets. Look for an ASTM sticker or certification on the helmet or packaging before buying. For snow sports, this test involves strapping the helmet to a head mold (think a mannequin with human weight) and dropping it on to 3 different anvil shapes at a speed that is about the speed a head would be falling from riding height. The impact forces cannot exceed 300Gs, which is around the minimal force that subdural hematoma and other serious traumatic brain injuries may occur. The helmet is also tested after being submerged in water, warmed, cooled, and exposed to UV in order to mimic possible temperature changes. European and Australian standards differ slightly, and many companies are making helmets to pass two or more of the standard testing protocols. 

Often when falling on the slopes, we are going much faster than the speed that a helmet is tested at, which may drastically change the performance. Concussions and some other traumatic brain injuries can also occur at much lower forces than the standardized testing limit, around 70-120 Gs. Helmet makers typically want to pass these tests, but are often trying to go above and beyond this testing such as incorporating rotational tests, or testing at additional force levels and speeds. If you are mountaineering or in the backcountry with significant overhead hazard, you may want to look for a helmet that is double certified as a climbing helmet to protect from rock and icefall.

Rotation damping systems: 

The current rage in helmet tech is rotational forces and how to minimize their impact. There is some evidence that rotational forces are more predictive than linear forces for both concussion and more serious brain injuries due to the shear forces rotation creates. Some helmets are designed to theoretically decrease the forces that we believe are causing concussions which are both linear acceleration and rotational acceleration. MIPS and WaveCel are the two most common systems that you will see on the market at the time of this post and these systems are covered below. 

MIPS and WaveCel are both relatively new technologies, and there is limited research on them. It is a difficult topic to research outside of a lab due to head impacts being much less common in skiing and snowboarding compared to something like football. One study investigated linear and rotational acceleration impacts in snow sport helmets comparing a regular helmet, MIPS, and WaveCel. They found little difference in linear acceleration across the board, but a significant reduction in rotational acceleration in the MIPS and WaveCel helmets. MIPS and WaveCel both outperformed one another at different impact sites, as well as speeds, but overall it concluded that the WaveCel helmet had the smallest concussion risk. 

The Virginia Tech Helmet lab has designed a test for assessing rotational forces by dropping the helmets on an oblique anvil and it will be interesting to see if this will be included in future updates of the ASTM standards. The lab publishes a helmet rating of 1-5 stars based on their testing and you can view a variety of sports helmet rankings on their website. To see those results, look up Virginia Tech Helmet Ratings.

MIPS:

MIPS stands for multi-directional impact protection system. They have partnered with most large helmet brands at this time, and is something you will see in a large range of helmets. MIPS is a system that inserts a low friction layer into the liner of your helmet to allow a rotational movement of the helmet about your head during an impact in the hopes to decrease the rotational forces exerted on the brain. There are multiple studies showing evidence that MIPS equipped helmets can reduce rotational acceleration with oblique impacts. Current MIPS technology is available in higher and lower end helmets, making it an affordable solution to mitigate rotational forces.

WaveCel:

WaveCel is a company that developed a cellular structure for helmets that can absorb forces in many directions, and is specifically designed to collapse and glide under a shear impact to reduce rotational forces. WaveCel found that slip-liner rotational dampers, such as MIPS, work well at lower speeds but when the forces are greater or faster the friction causes the slip liners to be less effective. WaveCel claims to work during high force impacts as well as low force falls. At this time, WaveCel is only available in a small number of snow sports helmets, and also makes their own helmet line. WaveCel tends to be more expensive than a similar helmet with MIPS. 

Replacing a helmet:

Industry leaders agree that helmets should be replaced after any crash. Modern helmets are similar to modern cars and are designed to crumple to reduce forces. With some impacts, the internal integrity of a helmet could be compromised after a fall or crash, and should be replaced as a precaution. This is one reason I believe that affordability is important with your helmet choice, you should be willing to replace it after a crash. Other than after an accident, there is little consensus around how old a helmet can be, but generally helmets should be replaced when they are around 5 years old. An older helmet isn’t necessarily unsafe, but time and wear may eventually degrade the integrity. Helmet materials and tech also continue to evolve and I believe that they are going in the right direction so having a relatively new helmet is a good thing. 

My recommendation:

1. Find a helmet that fits you well. 
2. Find a helmet in your budget, and ensure that you would be okay replacing it after a crash.
3. If you are able to afford a helmet with a rotational damping system, it is likely worth it for the possible reduced concussion risk. No helmet can predict how you will crash, and there is too little research to strongly support one system over the other. 
4. Consider other elements such as ventilation if you run hot or will be exercising hard, as well as double certifications if it will be used in mountaineering situations with overhead hazards.
5. Replace your helmet if it has any visible damage, or with any crash taken.
6. If you hit your head and are concerned about a concussion, come have it evaluated by myself or one of the team at MOST Physical Prep— the earlier concussion intervention starts, the better the outcomes. If you hit your head and are concerned about a serious brain or skull injury, go to a hospital. 

If you are interested in hearing more about helmet technology, I highly recommend the 5 part podcast series “Gear:30 Current state of helmet tech”. Other references I used to write this blog are listed below.

Bland, M. L., McNally, C., & Rowson, S. (2018). Differences in impact performance of bicycle helmets during oblique impacts. Journal of biomechanical engineering, 140(9), 091005.

Broglio, S. P., Schnebel, B., Sosnoff, J. J., Shin, S., Fend, X., He, X., & Zimmerman, J. (2010). Biomechanical properties of concussions in high school football. Medicine and science in sports and exercise, 42(11), 2064–2071. https://doi.org/10.1249/MSS.0b013e3181dd9156

Bottlang, M., Rouhier, A., Tsai, S., Gregoire, J., & Madey, S. M. (2020). Impact Performance Comparison of Advanced Bicycle Helmets with Dedicated Rotation-Damping Systems. Annals of biomedical engineering, 48(1), 68–78. https://doi.org/10.1007/s10439-019-02328-8

Cusimano, M. D., & Kwok, J. (2010). The effectiveness of helmet wear in skiers and snowboarders: a systematic review. British journal of sports medicine, 44(11), 781–786. https://doi.org/10.1136/bjsm.2009.070573

Daneshvar, D. H., Baugh, C. M., Nowinski, C. J., McKee, A. C., Stern, R. A., & Cantu, R. C. (2011). Helmets and mouth guards: the role of personal equipment in preventing sport-related concussions. Clinics in sports medicine, 30(1), 145–x. https://doi.org/10.1016/j.csm.2010.09.006
Haider, A. H., Saleem, Tz., Bilaniuk, J. W., Barraco, R. D., & Eastern Association for the Surgery of Trauma Injury ControlViolence Prevention Committee (2012). An evidence-based review: efficacy of safety helmets in the reduction of head injuries in recreational skiers and snowboarders. The journal of trauma and acute care surgery, 73(5), 1340–1347. https://doi.org/10.1097/TA.0b013e318270bbca