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By Cicely Enright
Nov 07, 2019
Where there’s snow, there’s the opportunity for fun.
For millennia, people have skied for recreation – or for work. Primitive versions of ski-like objects have been found in Russia, and wall paintings suggest their use in Xinjiang, now part of China.
Fast forward to today, and both skiing and snowboarding have grown exponentially in popularity.
Worldwide, more than 125 million people enjoy skiing and snowboarding, according to a 2016 International Report on Snow and Mountain Tourism. 66 countries now have lift-served recreation areas.
For more than four decades, an ASTM International group has worked to make skiing safer with the help of standards. Most recently, the committee on snow and water sports (F27) has added both terrain parks (the places snowboarders love) and water sports to its work.
The standards that have come out of F27 are an engineering success story. That’s how Irving Scher, Ph.D., P.E., describes it. Scher is chair of F27 and a principal and biomechanical engineer at Guidance Engineering and Applied Research in Seattle, Washington. “Our standards are very important to the industry and to consumers,” he says. “We’ve had a dramatic reduction in certain injuries that the committee was charged with addressing.”
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“I have always equated the two: standards and safety,” Scher adds. “Our main focus is improving safety.”
That improvement in safety has come with standards that range from procedures for testing the boot-binding-ski system function, procedures for testing the mechanical properties of ski equipment, and retail and rental shop procedures.
For example, an essential part in setting how an alpine ski-boot-binding system works requires: selecting release values, the moment at which the ski comes apart from the boot. That moment comes in a torque, or rotation, value set and kept (through maintenance) in the binding.
The practice for selection of release torque values for alpine ski bindings (F939) has guided the process since 1985, and it is used by binding manufacturers and ski shops. Its purpose is to help reduce the risk of injury from falling down or from impact with something or someone. And while the individual skier’s height and weight are the two most important release factors — and are covered in the standard — a recent revision to F939 draws attention to another dimension.
The revision, an illustration and text, notes (as included in the standard): “Choosing Your Release Preference Is Your Responsibility.” This allows users to adjust slightly the release settings to make them individual-specific.
“The whole change was consumer-oriented and [revolved around] trying to explain that difference to the general public,” says Scher. “That difference” explains how Types I, II, and III refer to release-ability, not skiing expertise (beginner, intermediate, expert).
For example, if the skier is just learning, an easier or type 1 release may be most appropriate. However, that easy release may also be a choice for more experienced skiers using new equipment to be sure the bindings release properly. Type II applies to settings appropriate for most recreational skiing. And Type III provides a decreased risk of inadvertent binding release and a corresponding increased risk of non-release (and is not recommended for skiers of 47 lbs [21 kg] or less).
The use of helmets for skiing has reduced head injuries significanty since 1995.
Another new direction for the F27 committee is alpine touring, a skiing style that requires bindings allowing the skier to go uphill as well as down. Other than the need for “skins,” which are typically nylon and are attached to the bottom of skis for better grip, the biggest difference with alpine touring comes with the heel binding that can be fixed for skiing downhill or can lift off the ski for walking uphill.
Of the situation today with alpine touring, Scher says, “The committee anecdotally is hearing of more injuries than we would like.”
The result is a proposed specification for release characteristics of alpine and alpine touring bindings (WK65030) now underway. The specification will establish the minimum performance requirements for various release scenarios. The standard, when completed, will complement the test method for measuring the quasi-static release moment of alpine ski binding (F504), which provides a series of ski binding lab tests to simulate the loads that could produce injury in skiing.
Helmets for snow sports, as for many other sports and recreational activities, help reduce injury. The National Ski Areas Association notes, “Increased helmet usage has proven to reduce head injuries, especially potentially serious head injuries.”
Writing about the role of such helmets in Skiing Trauma and Safety (STP 1582), Jasper Shealy, Ph.D., and co-authors looked at the “Sugarbush (Vermont) Study” over 17 seasons, from 1995–1996 to 2011–2012, a time when helmet usage increased from 8% to 84%. “We observed that helmets offer very effective mitigation for head injuries such as skull fractures and scalp lacerations. Increased use of helmets was also associated with a significant reduction in potentially serious head injuries as well as all head injuries.” Shealy, Robert J. Johnson, M.D.; Carl F. Ettlinger, and Scher co-authored the paper, and Shealy, Johnson, and Ettlinger have long studied skiing incidents in studies such as the Sugarbush study in Vermont.
A specification for helmets used for recreational snow sports (F2040) — skiing, snowboarding, and other alpine sports — focuses on performance requirements and not on restricting design, as noted in its scope. The standard includes tests for impacts and retention systems (what holds the helmet to your head) and refers to an additional standard for related headgear tests. That standard is the test methods for equipment and procedures used in evaluating the performance characteristics of protective headgear (F1446), and it covers the equipment, procedures, and basic requirements to test headgear.
The subcommittee on helmets (F08.53), part of the committee on sports equipment, playing surfaces, and facilities (F08) oversees F2040 and a number of other standards for helmets used in different sports and activities.
Richard M. Greenwald, Ph.D., an F27 and F08 member who is CEO and co-founder of Simbex, works on helmet standards. “Winter sports helmet standards are a worldwide effort and include F2040,” he says. “The helmet industry and researchers continue to evaluate injuries that do occur during winter sports in order to better understand the mechanisms of head and brain injuries in these sports, and to continue to improve both helmet technology and also safe rules and guidelines for participation to minimize injuries.“
Originally published in 2000, the standard is under continued review for any needed changes.
Greenwald says the standard has had a positive effect: “Having a standard in place prevents product on the market that does not meet the minimum requirements for use in winter sports. It encourages use of helmets designed specifically for winter sports.”
What F27 members have accomplished with ski-related standards that support safety for the sport, another group in the committee now looks to accomplish for snowboards.
Tracing either to Turkey’s “Lazboard,” named for the town where a snowboard-like device has been used for 300 years, or the 1965 “snurfer,” invented by Michigan engineer Sherman Poppen for his daughters by putting two skis together and adding a rope to one end, today’s snowboards have evolved more recently into their current popular form.
Like skiing, snowboarding gets the rider out on a slope in the snow, and it combines elements of skiing, skateboarding, and surfing in an exciting sport for spectators and participants alike. (While terrain parks were originally created to satisfy the demand for snowboarders who want to jump and slide on skateboard-oriented rails, this trend quickly expanded to skiing, which required resorts to respond with all-inclusive terrain park offerings.)
Snow sports terrain parks have become part of the F27 committee as the subcommittee on freestyle terrain jump features (F27.70).
“This was spurred by people outside the industry who recognized and had concern about injuries in terrain parks, and the industry got more involved,” Elia Hamilton says. “Our goal is to reduce injuries in terrain parks. We don’t want people to get hurt using jumps we have constructed.”
Scher agrees. “I think that has the potential to improve safety and not just in the U.S. but worldwide,” he says.
Hamilton, who leads the subcommittee, is vice president of terrain development at Peak Resorts and a former competitive snowboarder. He says he and the type of work he was doing grew up together, and he was learning while moving earth to build jumps. “I was in it [terrain park building] at a time when they were writing books about how to do it,” he says.
With his involvement in speaking at conferences and sharing his practical experience, he became involved in ASTM International to explore jump design standards.
The subcommittee began with a standard lexicon of terminology relating to snow sport freestyle terrain park jumps (F3237) to provide park designers, builders, ski resorts, accident investigators, and scientists with a common vocabulary to describe these features.
Now the group has turned its attention to a proposed method for measurement of snow sports terrain park jumps (WK68541). As the rationale indicates: To research jump design impact on the people who use the jump, measurements from different ski/snowboard jumps need to be comparable.
Part of the development includes inviting committee members to bring their measuring techniques to a mountain for real-world testing and benchmarking of a particular jump.
It’s about trajectories and landing forces, Hamilton explains. When you go off a jump and land: What force is acceptable for landing? What is the takeoff angle and speed of the jump? What impact do these angles and speeds have on the user?
Generally speaking, the trajectory and the angle of landing need to roughly match, so that the mechanics of the jump will allow safe landings. Perhaps artistically the angles look right, but the subcommittee is working towards numbers that indicate a jump will work. A range of measurements will likely result that indicate, for example, as the jump increases in size, other attributes need to change proportionally so that the jump continues to be successful.
“If we measure in such a way that we can re-create it at another place, another resort or trail, or another place on the same trail, then we’re increasing our success as an industry,” says Hamilton. “Then let’s apply that principle to every other jump at the resort.”
Scher is excited about the ongoing work in F27, which should continue to improve safety on the slopes. “We have had such success in improving safety because of the standards,” Scher says.
All those interested are invited to participate in the work of the snow and water sports committee. Contact Joe Koury, (+1.610.832.9804; jkoury@astm.org).
Like their cold-weather kin, bindings have an important role in water sports, which are currently being enjoyed by readers in the southern hemisphere.
Many of the same standards that apply to snow sports can be applied to water sports.
When the possibility of developing standards for water sports equipment came up, the similarity argued in favor of housing the new activity in the committee that is now snow and water sports (F27). It probably didn’t hurt that the chair of the new subcommittee on water sports (F27.80), Bethany Suderman, Ph.D., P.E., a senior biomechanical engineer, works with Irving Scher, F27 chair, at Guidance Engineering and Applied Research.
Suderman reflected on the new group: “Water sports would benefit from the experience of all these snow sports folks. We can take a lot, generally speaking, from the snow sports standards to include in the water
sports standards.”
“The industry came to us and said we’re really impressed with what’s happened with safety in skiing, and we want to do this for water sports,” Scher recalls.
Since its formation, the subcommittee is diving into a few standards, including one on a topic also important to snow sports: bindings.
A wakeboard even seems similar to a snowboard in shape, and both have bindings that connect the board and the rider. A proposed specification for wakeboard binding mounting area — requirements for locations for thread inserts and thread size (WK67020) — is now underway for these short, wide boards towed by a boat.
The insert positions have been different widths, the thread and screw sizes differ, plus insert patterns vary, Suderman explains. “So as a consumer, if you wanted to get a binding from one company and a wakeboard from another, you had to make sure they were compatible with each other because each manufacturer was doing it differently.”
The standard will address the issue with a specified insert area, and consumers will then be able to mix and match wakeboards and bindings.
In addition, the water sports subcommittee has entered the colorful world of inflatable towables — they’re not just tubes anymore. These inflatables typically give one to five passengers fun on the water and are designed to be pulled by a boat using a rope, the topic of another proposed standard from the subcommittee.
Suderman explains that riding an inflatable on the water requires little skill (no need to get up out of the water like water skiing or wakeboarding) and can be enjoyed by younger riders as well as adults. An inflatable would be attached to a boat with a tow rope and towed in semi-circles. “We often see a lot of injuries in tubing because of these factors,” she says. “The tow rope test is a good place to begin.”
The test information will lead manufacturers to test ropes in the same way so that breaking strength results, for example, can be compared accurately. That way, no matter who the consumer buys from, the rope will have been tested in the same way.
A third standard now underway in the subcommittee is another test (WK69725) to provide data about the resistance of a water ski to permanent bending and an indication of its basic strength.
More standards are planned, including a performance specification for the equipment, which will help in choosing the proper rope for the number of riders.
November / December 2019