Winter weather crashed into the bulk of the United States in the past few days, leaving its mark with travel delays, increased demand for energy and a very unexpected example of the effect of cold temperatures on thermoplastics.
The lesson came courtesy of the NFL on Jan. 13 during a playoff game between the Kansas City Chiefs and Miami Dolphins when the the outer shell of Chiefs quarterback Patrick Mahomes' helmet shattered during a play when temperatures in Kansas City were 4° below zero F.
"It was a first for me," he said in a post-game press conference.
Mahomes' preferred helmet is the Vicis 02, which has an outer layer designed to flex during impact and an inner foam layer providing further protection, according to the social media account of footballrs.network, a group following football equipment news in addition to teams and players.
The Vicis and two other popular helmet brands in the NFL — the Schutt F7 and the Riddell Speedflex — are designed to flex during impact but each helmet works in a slightly different way, footballrs.network noted. The Vicis has a larger impact area able to withstand tackles from multiple angles, but the extreme cold reached a critical point for the material.
To add to the situation, Mahomes added later, his backup helmet waiting on the sidelines was "completely frozen," so he had problems getting it on quickly, prompting him to briefly continue play with the broken helmet.