Helmets are designed to absorb impact energy and dissipate it safely – which is why every cycling helmet you see on a cyclist must meet specific crash test standards.
Bicycle helmets must display the month and year they were manufactured as well as which CPSC safety standard they adhere to; this ensures safe products.
Bike Helmet History
At this point, helmet design was rapidly developing. Although helmet use wasn’t yet mandatory in most countries, new technology was being created that revolutionized bike helmet production and design. Bell, for instance, created an infant/toddler model made out of all EPS foam material without an outer shell for maximum protection. Unfortunately, however, its weight prevented any actual use as it proved far too heavy for toddler heads.
They decided to experiment and came up with the concept of creating an outer cover made out of PET (milk jug plastic) and other lightweight, rigid plastics such as polycarbonate (PC). This enabled much lighter helmets while still offering significant impact protection and reduced skidding on pavement – both key factors when selecting a bicycle helmet. Giro quickly adopted this innovative technology and created the first “shell-less” helmet – the Prolight.
EPP (expanded polypropylene) foam was among the newcomers. It was similar to EPS but was more resistant to compression and slower to return to its original shape after impact. Due to its lightweight and rubbery feel, EPP was an ideal material to help dissipate energy more effectively during bicycle helmet crashes than its EPS counterpart.
Manufacturers also began producing helmets with sleeker appearances and started adding vents for cooling purposes. One significant development was the introduction of Bell’s Kinghead helmet, tailored explicitly for riders with giant heads; previously, people with this size had struggled to find helmets expressly designed to fit them – an issue finally addressed with this product’s launch in 1998.
As bike helmet use became more widespread, advocacy groups supporting its use began springing up around the world. Utilizing research data and personal narratives as evidence that wearing helmets saved lives or provided warning of what could occur without them, these efforts led governments and companies to mandate helmet use among bikers.
Bike Helmet Development
Bicycling may get all of the glory when it comes to sports-related concussions, but bicyclists are actually at greater risk. Stanford researchers have developed an innovative helmet design that inflates upon contact with pavement for added protection when riding your bicycle.
This technology is currently not commercially available, but the research could eventually pave the way for intelligent bicycle helmets that improve ventilation by utilizing sensing, electronics, and intelligent operation – including factors such as user environment and activity levels. Stanford helmet could even account for additional variables like ambient temperatures.
By the mid-1980s, bicycle helmet standards had become relatively established. Most manufacturers offered helmets with EPS foam liners and either ABS or polycarbonate hard shells, sometimes crushed and molded into these shells for an aesthetically pleasing effect; many designs offered poor ventilation, but this quickly improved as new technologies entered the market.
Expanded Polypropylene or EPP was one of the earliest innovations, appearing similar to Expanded Polystyrene but much less vulnerable to catastrophic failure, with more excellent resistance against cracks or holes than its counterpart EPS. This allowed designers to reduce foam usage for a given thickness while opening up vents, which is not possible with just EPS alone.
GECET foam was another innovation introduced during the early 1990s that enabled manufacturers to reduce weight by making more compact helmets with reduced liners and lighter weight liners. It features tiny cells for durability with reduced rebound and excellent lab test results, giving manufacturers more significant weight reduction potential and increasing performance.
At that time, numerous designs of bike helmets did not comply with ANSI or Snell Foundation impact protection standards and thus became subject to lawsuits against their manufacturers.
In the late 80s and early 90s, a process was developed for manufacturing in-mold micro shells – thin plastic shells that house expanded EPS foam – that allowed for more delicate, lighter helmets that were also stylish and safer. This technique allowed for innovative new helmet designs.
Bike Helmet Design
Cycling accidents don’t usually make headlines in the same way football collisions do, yet they can still be just as serious. Thanks to technological advancement and improved designs, cycling helmets have become much safer over time. Early designs used heavy plastic materials like polyethylene terephthalate (used for soda bottles and clamshell plastic), while new designs use light nylon with extra padding designed to absorb impact energy more effectively and reduce weight by using thinner plastic shells that offer additional padding that absorbs impact energy more effectively.
Helmets today are rigorously evaluated and tested to withstand multiple impacts in a short period. Drop tests involve dropping a helmeted dummy head onto multiple steel anvils; accelerometers and gyroscopes measure the acceleration and rotational forces of this process and generate ratings to indicate how well a particular helmet absorbs impact energies while dissipating them to prevent concussions.
Stanford lab researchers are creating an inflatable bike helmet inspired by Dr. Richard Schneider of the University of Michigan’s neurosurgeon department, who made it during football games to prevent head injuries.
He sold his design to Southern Athletic Company, a manufacturer of protective sports equipment. Later, this company changed its name to Bike and now makes helmets specifically for American football players as well.
Not only can the best bike helmets absorb energy and shock from multiple impacts quickly, but they can also disperse it quickly to limit any further damage from various strikes. This process is known as permanent compression; when an accident occurs, its inner padding compresses like the crumple zone in a car.
Road racer helmets use an advanced system reliant on internal frames with woven aramid cables attached to carbon fiber side panels that anchor into them to distribute forces in an accident more evenly across their surface area. Giro offers such a system in their Aries model under their MIPS Spherical name.
Bike Helmet Manufacturing
Helmets typically feature a soft padding layer in the center, with top and bottom layers of challenging, slick surface plastic material providing impact dispersion and aesthetics and comfort enhancements such as bordered plastic or padding added around its edge for additional protection and aesthetics. Finally, quality checks must be conducted against ISI standards to ensure compliance before bearing their brand’s emblem and being shipped off for sale.
Helmet outer shells are usually produced using blow molding, vacuum molding, or injection molding techniques. This involves heating raw materials to a high temperature before injecting them into a mold designed to match their desired helmet design. Once cool, this mold can then be dismantled into individual components that can then be assembled into one complete helmet.
Nolan uses EPS (Ethylene-Propylene) foam technology to line its helmets, with various densities available depending on head size. Nolan engineers the specific density required for any particular head size using CAD/CAM software to meet each helmet design’s exact specifications.
After attaching the liners and strap to the outer shell, they’re then stuck with glue, with the strap crossing across the lining for added strength and aesthetics. Finally, a transparent plastic coating is sprayed on to prevent scratching and fading caused by sunlight exposure.
A buckle is usually constructed of nylon or plastic with modern side-pinch clasps for secure closure. The hook should match all other elements of a helmet, with additional options such as visors, mirror and light mounts, speakers for sound, communications devices, and optional accessories such as earmuffs, vent covers, or bunny ears being available to add more personality and functionality to each helmet.