Walking on Ice

 I woke up this morning and looked out the window to find the ground covered in snow. I immediately dreaded walking outside, not ready to face the cold, but even less ready to face the ice that was almost inevitably on the ground. Like many Colgate students, I have fallen victim (pun intended) to the ice on Colgate paths around this time of year. Yet until recently, I did not realize the critical role that physics plays in making ice so difficult to walk on. 

    Friction is a force we encounter constantly, whether we realize it or not. When it comes to walking on ice, it is the lack of friction that we notice. Having the right shoes, the temperature, and whether or not you are walking on an incline all play a role in how hard it will be to walk on ice. A 1995 study by Gronqvist and Hirvonen looked at 49 different types of shoes and found that none of them were resistant to slipping on both dry and wet ice. This study demonstrates that it is extremely difficult to find footwear that is efficient for all types of ice conditions, which can fluctuate depending on temperature.

This problem stems from the fact that friction is basically eliminated on icy surfaces. When force is applied to ice, the ice melts a little bit on the surface, creating a thin layer of water on top of the ice, which is very smooth. This causes any object on it to essentially "float." This also makes the coefficient of friction extremely low and approaching zero (approx 0.05 for kinetic motion). According to the Global Floor Safety Network, "The USA Occupational Safety & Health Administration (OSHA) currently recommends that the static COF be at least 0.5 for all walkway surfaces under both wet and dry conditions. The Americans Disabilities Act (ADA) recommends the dry static COF of 0.6 on any flat or horizontal surfaces both wet and dry…" Thus, walking on ice can be extremely dangerous and can lead to injury. Having shoes with proper traction can help to increase friction by increasing contact with the ground, but no shoe is yet to be slip resistant in all conditions.

I was walking up the hill from the library (where I have fallen multiple times in icy conditions) and I realized that being on an incline made the ice even more daunting. Thinking back to lecture, I remembered that the frictional force is also lower on inclines. 

This combined with the lack of friction from the ice is the perfect combination to lead to a fall.

Works Cited:

Raoul Grönqvist, Mikko Hirvonen (1995) Slipperiness of footwear and mechanisms of walking friction on icy surfaces. International Journal of Industrial Ergonomics. 16:3, 191-200.

“Contact Us Now.” Global Floor Safety Network, gfsngroup.com/coefficient-friction/.