Helmets go Head-to-Head in NFL Testing

March 2, 2011
Will new helmet designs reduce injuries on the field?

NFL players suffered an estimated 159 concussions this past season. Even worse, health officials estimate that 50% of all school-age football players experience a concussion sometime in their school sports careers; and many receive several. That’s a concern because recent studies link concussion to cognitive problems and the early onset of Alzheimer’s disease. In fact, the National Football League became so concerned about head injuries that it commissioned tests on 11 new helmet designs from five manufacturers last year. The test results were controversial and brought little change in the helmets used by NFL players this past season. But that hasn’t stopped designers from coming up with better ways to protect player’s heads.

Test squabbles

Results from the NFL helmet tests were supposed to be confidential and released only to the manufacturers. But the underlying approach used in the test has become public. The NFL used two independent labs to impact test the new helmets. The new designs were then compared to a baseline of 12 older helmets — some new, some used — that went through the same series of tests. One controversial point is that these tests were not like those used by the National Operating Committee on Standards for Athletic Equipment (NOCSAE). In NOCSAE tests, the helmet is placed on a head model instrumented to measure impact forces on the head. Both are then dropped onto a steel-covered anvil with a 0.5-in.-hard rubber pad. The helmet is dropped 20 times, including two drops from a height of 60 in. onto seven different locations. A 60‑in. drop approximates a player running at 17.9 fps, or more than 12 mph, and hitting a flat surface that stops the head in less than 0.125 in. Impact-force measurements determine if a helmet can be certified to NOCSAE standards.

Over the years, consistent NOCSAE testing has led to significantly fewer skull fractures and subdermal hematomas by pointing the way to better helmet features. But several helmet manufactures complained about the recent tests.

“We need tests that are standardized, leading to reproducible, predictable results,” said Robert Erb, CEO of Schutt Sports in an interview with ESPN. Schutt is a leading manufacturer of helmets for youth football teams and the second most popular supplier to the NFL. “NOCSAE has that, and it has reduced injuries. The NFL’s new impact tests, sadly, will take years to get established. And even then, we are going to have to watch to see whether players who are supposedly taking less impact to their heads actually get fewer concussions on the field.”

More protests came from Vin Ferrara, the man behind Xenith and its X1 helmet. “The NFL is testing only for extreme circumstances that have little to do with concussions. They’re ignoring the lower-level impacts that might have a lot to do with the cognitive problems we’re now seeing in retired players,” he said. “And if this becomes the standard people look to, which it will because we’re talking about the NFL, it incentivizes manufacturers to make helmets stiffer, denser and more massive. If you only design for that and ignore the other 99% of hits, you’re making the problem worse. So whatever the results show, I don’t care. I don’t plan on changing the design of our helmets based on these tests. I don’t think they’re valid.”

Bert Straus, CEO of Protective Sports Equipment and designer of the Gladiator helmet, felt the tests were valid in that they let companies know whether or not their helmets were improving. “Unlike some manufacturers, I had no problem with the NFL testing. The intent was to show equipment managers, trainers, and players that new-generation helmets perform better and they should exchange old for new on the basis of the confidential test results. Critics of the protocol said these tests did not represent what actually occurs on the field. True, but no protocol can do that and that was not the intent. Our view of lab tests is that they are indicators and we use them as such. For example, our tests are always performed using a hard-shell helmet as a control. Therefore, relative values, not absolute ones, are the focus. When our relative lab values get better, it is reasonable to assume this will carry to the field.”

Despite what the tests showed, on-field behavior is the ultimate barometer. And when all was said and done, the NFL estimates that 75% of the helmets used this past season were made by Riddell, 23% by Schutt, 1 to 2% by Xenith, and a handful by Adams USA. NFL players are free to use any approved design. But designers continue to improve their helmets partly to address concerns of school-aged players and their parents.

Gladiator helmet
Bert Straus’ Gladiator helmet has been available to NFL players in various forms since the mid-1990s. But its overly large size never caught on among players or fans. In fact, it quickly earned the nickname “Great Gazoo Helmet,” after a Flintstone character with an oversized head. Nevertheless, a handful of players did use it, including Mark Kelso, a safety with the Buffalo Bills. He credits the brain-cushioning helmet with adding several years to his career after enduring several severe concussions.

Straus redesigned his helmet before submitting it to the NFL tests. He’s also upgrading some of its materials. One point of redesign concerned retention — the helmet could come off a player’s head or rotate out of position if he was hit in just the right spot.

To keep the protective headgear on the player, Straus added a safety lock to the chin-strap latching mechanism. The player must now insert his thumbs and lift while activating a release lever.

To stop inadvertent rotation, Straus changed the shock-mount connector. The mount originally connected using a key-shaped tab that aligned with a slot in the mask wing. He replaced it with an octagonal-shaped tab and slot. It provides more surface engagement or areas of resistance, and stabilizes the connection. Straus also changed the shock mount itself. It had consisted of two elastomeric rectangles with their long axis aligned to absorb shocks from frontal blows. He will soon have a circular mount that cushions blows equally well from any direction.

Straus is also evaluating a new material, a clear urethane called Quintium from the Hanson Group, for use in the face-mask portion of the helmet. It has proven capable of being struck by a 9-mm round without cracking, hopefully not an issue during NFL games. But tests still need to determine how much shock it can handle.

Straus is happy with the NFL testing, believing it let him show that his soft shell is a definite improvement over the traditional hard shell and that it will reduce head injuries. He intends to get his helmet certified by NOCSAE and expects to have his $400 helmets available this fall for NFL players and schools.

Bulwark helmet
Michael Princip, a designer at B/E Aerospace, has also designed a football helmet that has garnered comments from the football community. Called the Bulwark, it is said to reduce head and brain injuries. It discards the single-piece hard shell for a multipiece hard outer shell with measurable gaps between segments. The gaps acts as crumple zones to spread, delay, and reduce the initial impact.

The impact then travels to a series of pads made of thermoelastic urethane and EVA foam. The pads vary in thickness, density, and dampening rate, depending on where they mount. The pads have a relatively long fatigue life, long enough to last a full football season. Then they can be easily replaced, as can other components.

“The whole point is to make it easy to retrofit the helmet, so teams can replace padding and shell forms to accommodate players,” says Princip.

These pads are sandwiched between the outer and inner shell, with the inner shell made of a relatively hard plastic with good strength, light weight, and acceptable elasticity. The inner shell is perforated to further cut weight and improve air circulation.

Princip is investigating a new material, Nanovate, a nanometal polymer hybrid, for the outer shell. It’s a composite material that lets him get away from the traditional polycarbonate shell. It should also help meet his target of a helmet that weighs 3 lb or less.

To ensure his helmet looks good, he based his current design on previous-era MacGregor helmets as well as rugby headgear. He also incorporated features from other modern helmets, including extended jaw plates. They protect players from hits to the face.

Princip’s goal for his helmet is to find a design that can be put into production and sell for about $200. He wants to outfit an entire youth team with his helmets next season.

X1 helmet
Vin Ferrara, a one-time quarterback for Harvard University, was troubled by the use of traditional padding in helmets: They are fine for high-energy collisions, but not as responsive to medium and low-energy hits. This was the motivation for his new helmet, the X1.

Then, while squeezing and pounding on a nasal squirt bottle, Ferrara discovered it could cushion both soft and severe impacts. So he went on to model his Aware-Flow shock absorbers after the bottle, making them hollow and puck shaped. A properly sized hole lets air in and out, giving it a good response to a variety of impact severities.

A flexible shock bonnet holds the shock absorbers in place, and cinching down the bonnet puts the absorbers into proper position using an elastic cable.

The $350 X1 is manufactured by Ferrara’s company, Xenith LLC, and it has been used by thousands of players, from youth leagues through the NFL, but it has yet to be widely accepted.

Michael Princip, (Bulwark)
Protective Sports Equipment (Gladiator)
Xenith Inc. (X1) —

© 2011 Penton Media, Inc.

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