NFL Testing Validates Benefit of Guardian Caps

Football Player wearing Guardian Caps

The league tested and will now permit use of The Guardian Cap in NFL practices

Atlanta, GA – August 11, 2020 – The NFL and NFLPA have decided to permit the Guardian Cap NXT to be used by lineman in NFL practices. The Guardian Cap is a soft-shell cover that retrofits all football helmets. This announcement comes after NFL and NFLPA appointed engineers tested and released findings that showed a benefit to using Guardian Caps. 

The testing was conducted at Biocore, LLC of Charlottesville, VA, and the experimental design and data analysis were performed by NFL-appointed engineering consultants, Dr. Jeff Crandall, Dr. Ann Good, and Dr. James Funk in conjunction with two NFLPA-appointed engineering consultants, Dr. Barry Myers and Dr. Kristy Arbogast. The results were reviewed by the NFL Chief Medical Officer, Dr. Allen Sills and by the NFLPA’s Medical Director, Dr. Thom Mayer. 

Engineers simulated impacts sustained by NFL offensive and defensive linemen during games from 2015-2019, and found Guardian Caps to be beneficial. A summary excerpt of their findings from an official Memorandum are as follows:

  • “Add-on products were evaluated based on their ability to limit both rotational and translational measures of head motion relative to helmet tests without the add-on devices.”
  • “A statistical analysis of the weighted results indicated that helmets outfitted with these add-ons exhibited statistically significant improvements (on average 9% for the Guardian Cap NXT and 5% for the ProTech) over the bare helmets.”
  • “Results from centric (direct) and eccentric (glancing) impacts indicated that head impact severity was reduced in all conditions in which a Guardian Cap NXT was present on one or both helmets.”
  • The conclusion reads, “Based on the data from laboratory testing with a relatively small number of helmet models and impact conditions, the jointly appointed engineers believe that using the Guardian Cap NXT may reduce the head impact severity exposure for linemen, which may reduce the risk of concussion. Accordingly, the NFL and NFLPA will permit use of the Guardian Cap NXT for linemen during practices only.”
  • Finally, equipment staff and trainers from collegiate teams that have used versions of these products were interviewed to acquire qualitative feedback on on-field performance and usability of these products. In general, feedback from the collegiate teams that have used these add-ons for practices was positive. None of the teams interviewed reported issues with neck pain or fatigue as a result of using these add-ons. Further, no issues related to moisture or heat retention were reported.

“We are pleased that the NFL chose to evaluate Guardian Caps with their most up-to-date testing protocols. Their data showing that head impact severity was reduced in all conditions in which a Cap was present validates the feedback we’ve received for the past 10 years from players and coaches using Guardian Caps. We’re hoping that this research will encourage all levels of football to see the benefit that adding a Guardian Cap can have for players,” said Erin Hanson, Owner and Founder of Guardian Innovations.

“We started working with the NFL in 2017 when we won the inaugural NFL HeadHealthTECH Challenge – a competition funded by the NFL to encourage innovations in equipment. This led to continued discussions and testing with NFL engineers that led to the validation that our Guardian Cap, a decoupled add-on, could significantly improve the performance of current helmets.”  

About the Guardian Cap: Guardian was founded in 2010 with the mission of better protecting players through advancements in technology. Erin and Lee Hanson utilized their expertise from their material science business, the Hanson Group, to engineer, patent, and manufacture Guardian’s flagship product, the Guardian Cap, which was launched in 2011. After successful biomechanical testing and field testing, the company began marketing and selling in 2012. Fast forward and now 200+ college programs such as Clemson University (heading into their 8th season with Guardian Caps), Penn State, University of Texas, Texas A&M, University of Oklahoma, UVA, University of Washington, etc. have implemented Guardian Caps, along with 1500+ high school and 500+ youth programs all around the nation. For more information please visit:

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