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Updated: Feb 5, 2026

Modified Drop Tower Impact Tests for American Football Helmets
Published on: February 19, 2017
The effect of football helmet facemasks on impact behavior during linear drop tests
Katherine M Breedlove1, Evan L Breedlove2, Thomas G Bowman3
1Department of Health and Kinesiology, Purdue University, West Lafayette, IN 47907, United States; School of Kinesiology, University of Michigan, Ann Arbor, MI 48109, United States.
Abstract:
Football helmet certification tests are performed without a facemask attached to the helmet; however, the facemask is expected to contribute substantially to the structure and dynamics of the helmet through the effects of added mass and added stiffness. Facemasks may increase the peak acceleration and severity index; therefore, as-used helmets may not mitigate head impacts as effectively as certification tests indicate. Furthermore, the effect is expected to depend on the helmet design as well as the orientation and speed of the impact. This study examined the influence of the facemask on impact behavior in a NOCSAE-style linear drop test and the interactions with location, velocity, and helmet model. Increases in peak acceleration and severity index of up to 36% were observed when helmets were tested with the facemask.
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