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Snell officers clarify MIPS testing report

Summary: Clarification on MIPS testing by two Snell Memorial Foundation officers received by BHSI on March 10, 2021.

From: bmuzz@aol.com
To: info@helmets.org
Subject: Rotational Testing Clarification


One of our Snell engineers found the article on the bicycle helmets we did with and without MIPS. Randy Ching and I would like to clarify the reason that we did the research with the following letter.

Bill Muzzy


Dear Mr. Swart,

We're writing to provide clarification to a web article published on the BHSI website entitled, "MIPS and Sliding Resistance of Bicycle Helmets," (under the section, "Snell Foundation testing shows no improvement"). Although Bill Muzzy was (and remains) a Snell board member when he presented the findings of our study to the F08.53 subcommittee in 2018, this study was not conducted by the Snell Foundation. This research was a collaborative effort amongst the Snell Foundation (Snell), University of Washington (UW), and Specialized Bicycle Components, Inc (Specialized). The testing was conducted at the University of Washington's Applied Biomechanics Laboratory by two members of the Snell board (one of which was a former professor at the UW), along with one Snell employee. The helmets tested in the study (both standard and those equipped with the Multi-directional Impact Protection System -- MIPS) were donated by Specialized. The underlying goal of this project was to develop a repeatable test method that could measure and compare the effectiveness of bicycle helmets in reducing peak linear and angular acceleration components subjected to both normal and oblique impacts using a standard twin-wire (guided-fall) helmet test rig.

The methods development and testing was performed at an independent university laboratory with their equipment and instrumentation in hopes that the test method could be easily and inexpensively replicated by other laboratories that use standard twin-wire helmet test rigs. It was not the intent of our study to single out or expressly show that MIPS offered little improvement in angular performance over a standard helmet, but rather to examine whether a reasonable test method could be developed for evaluating helmet performance in reducing angular acceleration resulting from oblique impacts. We believe our goal was accomplished.

Snell is currently developing its own angular helmet test method to facilitate oblique impact testing. This will enable future evaluations of helmet performance under angular test conditions and may provide a basis for comparison with the findings reported in our previous 2018 study.


Bill Muzzy & Randy Ching