Relatively, the most common cause of slips and accidents in winter is black ice. Black ice is a thin coat of glazed ice on a surface. And it isn’t black—it’s actually clear, but it takes on a dark colouring from the pavement below it. Because it is so thin, it is often invisible to the human eye.
Black ice can form in many ways, but the most common ways are melting snow and freezing rain.
Be extra cautious when there is a big fluctuation in temperatures. For instance, when the temperature rises above freezing during an afternoon, causing the snow to melt, and dips below freezing overnight, it causes a thin and invisible layer of water to freeze.
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