SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: http://read.uberflip.com/i/1342270
Helmet Technology 2021 Head and Neck Protection Story by Stuart Bourdon Photos courtesy Snell Foundation, Impact Racing, Simpson, RaceQuip, and NecksGen. During some recent conversations about helmets and safety equipment, it was suggested that the only thing two off-road racers ever agree on is that the third guy is doing it wrong. The off-road racing community, especially those involved in SCORE Off-Road Racing desert races, are always willing to let each other know what they think is the right way to do something. That friendly willingness to share “opinions” about what’s best extends to all aspects of the sport, including safety. Off-road racing has come a long way since its infancy. It used to be a sport of jeans and t-shirts. Now, Trophy Trucks are putting out 1000-plus horsepower. Pit stops are measured in seconds. Many gallons of fuel are dumped in tanks. Engines are running and everything on the truck is hot. Even fuelers are wearing fire suits and full helmets. Much of that growth and progress in safety equipment, specifically head and neck protection, is due to feedback and cooperation between racers, builders, performance product manufacturers, and safety organizations that continue to keep standards high. SCORE Requirements Current SCORE requirements state all helmets must be full-face design in good condition with current Snell, SFI, ECE, or FIA certification. For all four-wheel vehicle competitors, the helmet must be worn with a certified head and neck restraint (HNR) set up. SCORE Tech Director Dan Cornwell said, “Almost all the truck or buggy drivers (as well as UTV competitors) are wearing carbon fiber full-face helmets with incorporated face shields and fresh air systems.” “A lot of the motorcycle riders are wearing a lighter weight ‘European’ style with a chin guard to protect the jaw and mouth,” continued Cornwell. “It’s worn with goggles. This style is often considered ECE-approved. The motorcycle helmets can be current ECE, SFI, or Snell certified–any of those three will be accepted.” Cornwell added, “The new Snell helmet standard for all SCORE racers is SA2020, so SA2010s are out, and I’ll look at SA2015s on a case-by-case basis.” Standard Setter Snell Director of Education Hong Zhang gave us some background of the Snell foundation’s history and mission: “The foundation was created in 1957 after well-known SCCA driver William ‘Pete’ Snell died from sustained head injuries when his car rolled over during a race. Dr. George Snively was a racer and track physician who believed Snell’s death was the result of poor helmet design. Dr. Snively began a research program to study head injuries, and those findings led to the creation of the Snell Foundation.” The Snell Foundation continues to research and perform testing today, and its certification of helmets for auto and motorcycle racing is required by motorsports organizations around the world. Edward Becker is Executive Director of the Snell Foundation and is responsible for the operation of the helmet testing and certification programs. He described one impact testing method, stating, “We use a range of ISO head forms (to represent different head sizes and shapes) that have a decelerometer inside to keep track of the peak deceleration as the helmet and head form is slammed into impact surfaces. If it doesn’t exceed a given level of deceleration measured in Gs, the helmet as far as we’re concerned passes that test. We also perform fire testing, but motorcycle helmets do not require fire testing.” Becker continued, “We don’t tell manufacturers how to make helmets, but there are standards to meet. We do the testing and certification of those standards. One of the puzzles for helmet manufacturers is balancing between having a liner that is not too soft but not too hard. The idea is to slow the movement of the skull (and brain) inside the helmet during an impact without letting it stop too quickly or letting it crush all the liner and hit the inside of the hard shell.” Helmet Shell Science Helmet manufacturing is a fairly mature process and the basic materials used have been around for decades. However, new ideas and shapes, better shell materials, and different blends of liner materials are always being tested. Advances in support systems including integration capability of in-helmet communication systems, hydration, and even driver physical telemetry, are either currently available or on the horizon. There are two basic criteria to balance when designing a helmet— impact resistance (things coming through the helmet) and energy absorption of that impact. For the most part, the shell is meant to handle a hit while the inner liner absorbs the energy. Ben O’Connor from Impact Racing told us, “Carbon fiber and carbon/Kevlar composites are being used in our new helmets to increase impact resistance and reduce weight on the driver’s neck. The lighter weight helps with driver fatigue during long races.” Roger Mealy, Marketing Director at RaceQuip, walked us through some of its latest helmet technology. “RaceQuip helmets are made using a pre-preg (composite of pre-impregnated fibers and partially cured polymer matrix) process to create a thinner, lighter, and more consistent shell without sacrificing strength. To meet Snell SA2020 guidelines, we increased the amount of Kevlar in the shells and introduced several new carbon fiber helmet models.” The Snell SA2020 standards, “allowed us to redesign our helmets and make a few upgrades,” said Steve Russell from Pyrotect Safety. “The face shields are now held in place with a more-positive latching system, and we redesigned the internal airflow pattern of our new helmets.” Inside the Helmet Controlling the movement of the head inside the helmet is vital. As the foam inside the helmet compresses from head movement during an impact, it slows skull movement and absorbs energy. Compression and absorption also help slow brain movement, which is especially important in multiple-hit situations such as rollovers. Manufacturers offer blends or layering of different liner foams. Expanded polystyrene (EPS) and expanded polypropylene (EPP) are most commonly used. EPS offers a very good energy absorption solution on a single hit. EPP also has good initial hit performance— maybe not as good as EPS— but it offers superior performance in secondary hits. Impact Racing’s O’Connor told us, “We use EPS and EPP in different parts of our new carbon and carbon/Kevlar helmets. We also offer ear cups for our helmets to protect drivers from engine and exhaust noise.” Russell at Pyrotect added, “We are now using a four-pad corrugated headliner system. That allows air to flow better over the top and down into the sides of the helmet.” Protect the Neck Head-and-neck restraint technology has kept pace with advancements in helmet technology and continues to improve in both product performance and comfort. Charlie James at Simpson Race Products said, “We use 3D modeling/printing and design of experiments (DOE) software to help develop products. Our updated HNRs better reduce the load in a frontal impact. Impact resistance and internal energy absorption are key factors in our new Simpson and Stilo Snell helmet.” Space-age materials also play a big part in NHR design. Jeff VanStone told us, “Our newest NecksGen head-and-neck restraint is made from hand-laid carbon fiber and reshaped to fit a wider variety of shoulder shapes. Hand-laid carbon allows the use of honeycomb in the product, making it lighter (less than a pound) and more comfortable.” “Today, the entire body is protected by helmets, seats, harnesses, and clothing accessories. But a weak point persists— the neck and the cervical area.” Émeric Caltagirone from Stand 21 added, “The latest FIA standard update created a static tensile test with a minimum five-second hold time and force of 7,000 Newtons (about 1,754 pounds). We use a variety of materials including injected resin, injected resin reinforced with carbon fiber, and full carbon fiber. Technology like traction bench testing and ultrasonic structure control help us develop products to meet the standards.” Helmet and HNR Dos and Don’ts Scott Steinberger from PCI Race Radios is experienced in selling safety equipment, including helmets and helmet accessories like integrated communications systems. He offered, “The lightweight carbon fiber helmets are by far the most popular. Be sure whatever brand helmet you buy has products and accessories available at the race. If you bust a face shield and can’t find a replacement at the event, you could be sitting out the race.” Roger Mealy of RaceQuip suggested, “Just because you wore a large helmet in one brand does not mean you will wear the same size in another brand. Since helmet fit (snug but not too tight) is so important to its function, it’s critical to get it right. Measure around the crown of your head (one inch above the eyebrows) and compare that to the specific manufacturer’s size chart.” NecksGen’s VanStone said, “Sometimes people think because it’s shaped like the back of the neck, the HNR is supposed to go right up against the spine. It’s supposed to be on the shoulders and back. Also, everybody isn’t built the same, and helmets and HNRs are not all built in the same shape. Find an HNR that fits comfortably and always properly adjust the tether between the HNR and the helmet.” We asked all the manufacturers and experts interviewed what to look for when buying a helmet and head and neck restraint device, and how to best use these products. Every manufacturer highlighted here can offer instruction on how to properly wear their products and offers products that meet or exceed one or more of the testing and certification standard organizations. They all agreed the most important thing anyone should ultimately be looking for is the current standard certification label or sticker, and that no matter where you buy your helmet from, safety should always come first. SJ