Your professor could be testing the hockey gear that you bought this season. Researchers in the McGill Ice Hockey Research Group perform tests for some of the biggest companies on the market, and are involved in numerous projects involving the safety and efficiency of ice hockey equipment.
One of the lab’s major projects is equipment testing. PhD candidate Ryan Ouckama and Dr. David J. Pearsall, of the McGill department of kinesiology and physical education, perform impact tests to compare ice hockey helmets by subjecting them to various types of forces. Companies send new helmet designs to the McGill Group for testing to determine if the equipment is safe for game use.
One way Dr. Pearsall tests a helmet is with the drop test.
“You have a controlled vertical drop and … in the head form … [you have] an accelerometer. The impact event must stay below a criterion threshold acceleration on impact that is considered unsafe in terms of what the head can sustain without traumatic skull injury,” he said. “More specifically, well below the 50 per cent risk level.”
The drop tests are performed under a variety of conditions, such as different temperatures and repeated impacts. Lower temperatures generally reduce a helmet’s impact cushioning effectiveness, but some helmets actually perform slightly better in the cold. These tests ensure that designers can meet players’ needs by scrutinizing the equipment under realistic conditions.
Dr. Pearsall’s lab also investigates the effectiveness of different foam densities inside of hockey helmets, comparing a range of materials including vinyl nitrile and polypropylene. The foam is designed to be crushed or deform upon impact. “The basic function of the foam is … to absorb as much energy instead of your head,” Dr. Pearsall said.
Ouckama uses drop tests to measure the impact of a one metre drop with an array of sensors. He translates that data into a map showing force over the whole area of the foam.
Specifically, Ouckama is examining helmet resistance in two categories: focal force, which measures its ability to withstand impact in a specific area, and the maximum acceleration of the entire head. Helmets that are strong in one category aren’t necessarily strong in the other, which shows that there is some variability between helmets’ performance in preventing focal injuries versus their effectiveness against general blows to the head.
By next fall, Dr. Pearsall is hoping to extend the scope of the research with the hockey lab into other areas of investigation, such as the lower body protective equipment—bruising and fracture of lower body are among the most common sports injuries. He will apply the mapping technology to observe the equipment’s effectiveness in protecting soft tissues, like muscle and skin, hopefully finding areas where the gear can be improved.
The ice hockey lab has an immense number of projects, including performance of helmets and body gear, tests for international agencies, and other prospects like concussion research. “We plan to continue studying impact mechanics to better understand the mechanisms that relate to injury as well as identify means to reduce those injury risks.” Dr. Pearsall said.
