If you’re a Canadian, falling—rather, not falling—on an icy street or sidewalk is likely top of mind this season.

While salt and sand help make slippery surfaces safer, there’s always that patch of black ice that can catch you by surprise.

Or maybe it’s a sheet of ice hiding under a dusting of snow as you step out of your car.

According to Toronto’s University Health Network (UHN), more than 20,000 Ontarians visit the emergency room every year due to injuries related to falling on ice or snow.

So it’s not surprising to learn that many people avoid the out of doors as a way to cope with dangerous winter weather.

On one hand, this stay-inside-where-it’s-safe strategy makes sense. On the other hand, too much indoor inactivity can also lead to weight gain and muscle loss (along with mild panic when shorts-and-T-shirt weather arrives)..

One solution to this slippery-surface issue is to wear reliable boots that keep you standing solidly on your feet.

Researchers at UHN’s Toronto Rehab have developed a “snowflake” rating, which rates boots from zero to four snowflakes—zero snowflakes for super-slippery and up to four snowflakes for super-grippy.

The snowflake system tells consumers how boots will perform on ice before they commit to a purchase. Brilliant!

(Spoiler alert: huge numbers of test boots—including some very popular brands—received zero snowflakes.)

Read all the details here, and read more here.