Cycling Helmet Reviews, Helmet safety, KASK, MIPS, Tech, Tech features, Virginia Tech -

Kask puts MIPS on notice with new WG11 rotational impact test

Kask puts MIPS on notice with new WG11 rotational impact test

Italian company Kask has long enjoyed a cult-like following for its expansive range of stylish and feature-laden bicycle helmets, but one conspicuous omission has been the lack of a MIPS (multi-directional protection system) low-friction liner to help mitigate rotational impact energy during a crash. The technology was first used in a cycling helmet by Scott almost ten years ago, and it didn’t take long at all before it found favor throughout much of the rest of the industry amongst a growing list of brands continually striving to pitch their helmets as offering cutting-edge safety features. 

Kask, however, has been a notable holdout. Although there has certainly been speculation that the brand simply didn’t want to pay MIPS a licensing fee, the company has been telling people for years that it simply didn’t believe in the efficacy of the concept.

“After four years that this technology is on the market, it is still not proved that it makes the helmet safer. After various tests done internally and with an external company and safety certification agency, we realized that it doesn’t really add any value to the security of the helmet, while for sure it adds weight and provides less comfort to the helmet.”

MIPS has become widely accepted as almost a must-have when it comes to cycling helmet safety features, but should it be that way? Photo: James Huang.

That statement was sent to a customer in 2016, and in the six long years that have passed since then, the powerhouse that is the collective MIPS marketing machine (bolstered by third-party test results from organizations such as Virginia Tech – and yes, even media entities such as CyclingTips) has only continued to further cement in the public mind the idea that rotational impact protection is critical to preventing traumatic brain injuries. In the meantime, Kask’s continued decision not to include MIPS (or any similar technology) on any of its helmets has often been taken as stubborn obstinance that has almost certainly impacted their sales figures. 

Kask has over the past few months been teasing this long-awaited test protocol – officially dubbed the “Kask rotational impact WG11 test” – and it’s finally now shining a full-blown spotlight on what it is and why it’s significant. 

“There has been some confusion where a helmet without a specific anti-rotational technology is defined as an unsafe helmet,” explained Kask product director Luca Viano. “This is not true. A helmet’s protective performance should be judged by the results it can achieve in impact tests, and not in light of the reason it features or doesn’t feature certain technologies. Since no universal methods exist today to measure the response of cycling helmets against rotational impacts, we designed our own.”

Not surprisingly, Kask says the new WG11 test protocol shows that its helmets do just fine in terms of attenuating rotational impact energy. But what’s more surprising is that Kask isn’t exactly saying that MIPS is wrong. 

Making heads and tails of rotational energy tests

By all accounts, the effect of rotational impact energy on traumatic brain injuries isn’t some made-up phenomenon. Plenty of research seems to widely support the notion that concussions and similar injuries aren’t only caused by linear impacts, but also by crashes where the rider’s head is violently twisted or spun when hitting the ground. It’s data that’s relatively easy to produce in a lab and hard to refute (at least in concept), and MIPS proponents have certainly done an excellent job of getting that message across. 

Kask isn’t arguing with any of that. But in a more general critique of the bicycle testing world overall, the Italian company is essentially saying that we’ve been doing it wrong all this time. 

Helmet testing invariably requires some type of headform inside the helmet. However, headforms are not all created equal.

The key differentiator of Kask’s WG11 test is the headform that’s used to collect the data. Whereas the so-called Hybrid III headform is more or less the industry standard when it comes to testing cycling helmets, Kask is instead using a far newer headform called EN960. According to Kask – and its independent test partner, Newton Laboratory, in Milan – the EN960 headform’s slicker surface is more representative of how the human scalp (not to mention hair) behaves during a crash, acting as a natural shear layer that helps to attenuate rotational energy. You can feel that natural layer just by moving your scalp across your skull with your fingers, and it’s something skeptics of the MIPS concept have long asked about. 

In contrast, the more common Hybrid III headform features a rubber-like surface that’s far tackier – almost as if you’re attaching a helmet directly to your skull.

The KG11 test itself isn’t anything out of the ordinary. An instrumented EN960 headform is fixed within the test helmet, which is positioned on a guided sled situated approximately 2 m above the impact point. Target impact speed is 6 m/s. The steel impact anvil is flat, angled at 45°, and covered with 80-grit sandpaper to repeatably induce rotational force upon impact. Inside the headform are three linear accelerometers and three angular rate sensors, all transmitting wirelessly to eliminate any unwanted effects of an attached wiring harness. Each helmet model is tested at four different impact points.

Among the data collected from each round of tests are two key metrics: HIC (Head Injury Criterion) and BrIC (Brain Injury Criterion). A HIC result greater than 1,000 indicates a high probability of skull fracture, while a BrIC score greater than 0.68 likewise indicates a high probability of brain injury.

Needless to say, this is one test where you’re hoping for lower marks, not higher ones.

Test helmets are first secured to a headform, with impact points identified using a laser jig. The helmet and instrumented headform are then placed on the test platform, which is dropped from a height of approximately 2 m on to a sandpaper-covered and angled anvil so as to induce a rotational moment.

So how did Kask’s helmets do? Kask didn’t provide HIC scores for its helmets, although modern bicycle helmets generally do very well there so that’s not a cause for concern. But in terms of BrIC, Kask says none of its helmets have scored above 0.39, which roughly translates to a sub-30% chance of surface abrasions or other superficial injuries according to the industry-standard AIS (Abbreviated Injury Scale).

In other words, Kask helmets apparently perform very well when it comes to rotational impacts.

Stacking the deck

It’s important to note here that Kask saying its helmets are safe when it comes to these sorts of crashes is not the same as the company saying MIPS and similar technologies aren’t effective. Instead, Kask is suggesting that while MIPS and other MIPS-like devices likely don’t hurt, they don’t offer any meaningful additional safety benefits, either.  

“We based the design of our test on both ECE 22.06 [the latest European motorcycle helmet test standard – Ed.] and papers that suggest that the use of a headform with a higher coefficient of friction than a human head would overestimate the head response during rotational impact,” said Viano. “Therefore, this behavior could exaggerate the contribution of anti-rotational technologies.”

The beige headform at right is the Hybrid III, which is very commonly used for testing bicycle helmets. Its rubbery surface is much tackier than the slick surface of the EN960 headform at left, though, which can dramatically affect the results of rotational impact tests.

In other words, Kask isn’t remotely suggesting that MIPS is doing anything nefarious like fudging test results. Tests are tests; data is data. But Kask is very explicitly saying that any headform that doesn’t mimic a human head’s natural shear layer will artificially amplify the effects of a supplemental shear layer. In other words, if a helmet can’t slide on a headform like it would on a human head, a helmet that doesn’t incorporate a MIPS-like feature isn’t going to test well, and any helmet that does include a MIPS-like feature might appear to offer more of a safety advantage than it really does.

Caveats and questions

If you take Kask’s WG11 test story at face value, one key takeaway is that the company’s helmets provide excellent protection against traumatic brain injuries despite not incorporating any sort of dedicated MIPS-like device. That’s great. But there are still plenty of questions, too.

If Kask’s WG11 protocol generates more realistic test results, that’s an achievement that should be universally lauded. However, those sorts of tests are also only genuinely useful to consumers in context, which is why third-party data such as from Virginia Tech has become so powerful in recent years. In other words, it’s great that Kask’s helmets perform well according to WG11. But how does Giro do, or Bontrager, or Bell, or Specialized, and so on? Kask likely has conducted those benchmark tests, but the company declined to confirm as such or provide any data.

The new Giro Eclipse features the latest MIPS incarnation, called MIPS Spherical. Kask’s WG11 rotational impact energy test may suggest that these sorts of devices aren’t entirely necessary, but without additional information, that doesn’t mean they don’t provide additional benefit, either.

There’s also the question of wider industry support for WG11. Currently, fellow Italian brands Rudy Project and LAS are on board with the initiative, and helmets from all three brands will feature a conspicuous “WG11” round red icon moving forward. Neither of those other two brands are particularly heavy hitters in the market, though, so I contacted several bigger brands to see if they might throw their weight behind WG11; none had yet responded by press time. Regardless, Kask has made it very clear that it hopes WG11 is broadly accepted.

But there’s still that big yellow elephant in the room. 

Let’s take all of Kask’s claims at face value for a moment here, that a dedicated low-friction liner really isn’t as critical to brain injury protection as we’ve been led to believe for the last ten years. However, how would MIPS-equipped helmets perform on average compared to helmets without MIPS-like features using that same WG11 protocol? After all, the ultimate goal with cycling helmets isn’t to just pass some test, it’s to ace them with as wide a margin as possible. Put another way, it’s great that Kask’s helmets do so well in the WG11 rotational impact test protocol without any sort of dedicated low-friction liner – but would they do even better if they had them?

That is something I asked Kask directly, and while one might rightfully assume the company has conducted those benchmark tests, Kask wasn’t able to provide that answer.

“Regarding the performance of MIPS if tested with an EN 960 headform, I cannot answer that question,” Viano told me. “You should ask MIPS representatives directly.”

So I did, of course, although I hadn’t been able to coordinate schedules for a chat by the time this story was published. 

I did hear from the folks at Virginia Tech, though, and while they seem to support the idea of the WG11 protocol, there are some questions, too.

“The Hybrid III headform does have a high coefficient of friction and that certainly makes a big difference,” said Barry Miller, director of outreach at the test lab. “I don’t know about the EN960 as we don’t have that in the lab yet. We use the NOCSAE headform that is designed for sport helmets and it is a bit tacky, but much lower than the Hybrid III. Our helmet/head coupling is fairly tight if compared to a full head of hair. Obviously, a full head of hair and scalp provides a natural slip plane and thus helps reduce friction and improves the decoupling of the helmet and head. It is difficult to say if MIPS or other rotational technologies would enhance performance over and above a full head of hair, but [they] likely can’t hurt.”

And while I may not have been able to talk about WG11 directly with MIPS yet, a recent journal article co-authored by MIPS co-founder Peter Halldin and published just last month provides some intriguing insight in the meantime. Among the key excerpts is this little nugget (emphasis mine):

“Our results suggest that [moments of inertia] and [coefficients of friction] have significant effects on headform rotational kinematics, and consequently brain deformation, during the helmeted oblique impact. Future helmet standards and rating methods should use headforms with realistic MoIs and CoF (e.g., the Cellbond headform) to ensure more accurate representation of the head in laboratory impact tests.

This is getting interesting, folks. 

I want to believe

Just as some have been content to question claims regarding MIPS and similar technologies, others will certainly be skeptical about Kask’s WG11 initiative, perhaps dismissing it as some marketing-driven ploy to justify the company’s refusal to play ball. I mean, of course, the company would prefer to not pay MIPS a licensing fee for its technology, right?

However, keep in mind that it would have been far easier for Kask to just hop on the MIPS bandwagon instead of devoting all this time and money to WG11. It could have just tossed MIPS liners into its helmets like just about everyone else and called it good. But now we know why it didn’t, and in my opinion, the story seems pretty compelling.

Helmets have certainly come a long way, but with a renewed focus on safety in recent years, any advancement in testing should be viewed in a positive light.

Unfortunately for Kask, perception all too often trumps reality, and MIPS has one hell of a head start right now. Will any of this turn the tide of consumer perception? Time will be the ultimate decider, but this reader comment from my review of Kask’s third-generation Mojito3 helmet is telling:

“It’s almost unbelievable that there have been so many studies on these slip liners and no one has bothered to consider how skin and hair interact with the helmet. One would think that this would be as important as the MIPS liner itself. Of course, it’s not surprising that Kask would say that since they don’t offer MIPS helmets (or with similar technologies), which saves them some money, but all the MIPS hype has been generated by companies who profit from it, so it’s quite hard to know which stance to trust more.”

More information on Kask’s WG11 test protocol can be found at www.kask.com.

Read More

Tags