(Another in an Inside Slant series that will appear regularly during the 2014 offseason.)

For decades, most NFL players have worn helmets that were developed before brain trauma was well-understood. The primary purpose of standard football headgear was not to prevent concussions -- deemed minor injuries at the time -- but to provide a protective barrier against skull fractures.

So it's not surprising that one of the most substantive innovations in this realm came from a man who experienced none of the preceding context. Bill Simpson spent most of his professional life around race cars, first as a driver and later as a safety advocate who famously popularized fire-resistant race suits. He didn't attend his first NFL game until 2010, when he was 70 years old, and was stunned to see an Indianapolis Colts player carted off with a head injury.

"I asked a friend of mine who was a coach and was told, 'That's part of football,'" Simpson said recently. "He said, 'It happens all the time.' I said, 'How can that just be accepted?'"

Simpson set out to design, build and market a helmet in which technology zeroed in on concussions as much as previous models had focused on skull fractures. The result is a helmet so fundamentally different -- most notably, it is half the weight of a traditional helmet -- that it has struggled to gain traction in the NFL. About 20 NFL players have tried the helmet over the past two seasons, according to national sales manager Ashlee Quintero, and for now, Simpson's SG Helmets are focused on youth football, where the politics of branding is less intense and familiarity with equipment less of an issue.

"We encountered big resistance to change," Quintero said, "which we understand. You've worn the same kind of helmet for 15 years. Why change now?"

Simpson consulted with researchers who contended that football concussions occur more frequently from rotational acceleration -- the brain hitting the side of the skull as the head moves -- than blunt force. He eschewed the hard plastic that football helmets have traditionally been built with and instead used a blend of carbon Kevlar, which is flexible and intended to absorb the force of a hit.

The photo shows that an SG helmet appears similar to standard models. But carbon Kevlar is by definition a lighter material, and the weight of an SG helmet is between 2.4 and 2.6 pounds for adults and 1.8 pounds for youth. A standard football helmet weighs between 4 and 6 pounds.

"It's raw physics," Simpson said. "You remember force equals mass times acceleration? If you have less mass, the force of the blow to the head from the collision is going to be lower."

Simpson's helmet is certified by the National Operating Committee on Standards for Athletic Equipment (NOCSAE), and it received a four-star rating (out of five) from an evaluation system developed by two universities. It's one of 18 helmets featured on a poster that looks like this and will hang in NFL locker rooms this season.

A Purdue University graduate student conducted tests that concluded that SG helmets disperse force before it reaches the head at least 50 percent better than traditional models. According to Quintero, there were 19 reported concussions among the 1,500 helmets used last season at all levels of football.

"It's not perfect," Quintero said. "Nothing is. But you look at that and say, 'Even if those numbers are under-reported, and even if it's three times as many, you're still at less than 5 percent of players sustaining concussions."

(For context, consider that the NFL's report of 228 concussions last season worked out to about 10 percent of its players.)

These numbers point SG in the right direction, and its innovation has entered the market at a time when the politics of brain equipment are changing in the NFL. Players have always been allowed to wear any helmet approved by the NOCSAE, but an exclusive contract between the league and Riddell made its helmets the default selection of many. If a player used another brand, that company's logo could not be visible.

The league terminated that deal in the fall, disassociating itself with the idea of endorsing a helmet of any kind. It's worth noting that SG's most notable NFL client, former Colts center Jeff Saturday, was the president of the NFL Players Association and thus unlikely to be influenced by corporate branding pressure. Saturday retired after the 2012 season.

To this point, however, persuading more than a few NFL players to change to a lightweight helmet has been a challenge. The youth market might be the most fertile ground for (eventually) impacting the NFL.

SG's 1.8-pound youth helmet is a more appropriate weight for children, according to Simpson. It's easier to keep their heads up, an important emphasis of the NFL's USA Football, and Simpson also believes its lightweight nature will dissuade players at all levels from hitting with their heads.

"I tell that to coaches every time I talk to them," he said. "They're not putting a weapon on their head and ours doesn't feel like one."

If nothing else, the dissolution of the Riddell contract will raise awareness of the diversity of choice available. In this case, knowledge begets competition, which begets further innovation, which -- one would hope -- takes football to a safer place.

You might have noticed this story last week about Riddell's new SpeedFlex helmet. Its defining characteristic? A flexible panel on the crown designed to disperse the force of impact. Flexible? Disperse? Sounds familiar.