With vast areas of Canada currently in the midst of a polar vortex, remaining safe in these frigid conditions is paramount.

Extreme cold has blanketed parts of Saskatchewan, Manitoba, Ontario and Quebec, where temperatures in some areas are expected to reach as cold as -55 degrees Celsius with the wind chill. Temperatures that low can freeze exposed skin in less than two minutes, according to Environment Canada’s wind chill index.

George Sharpe knows the risks of a deep cold all too well. About 10 years ago, the Saskatchewan native’s hands froze in -50 degree weather after he took his gloves off to change a flat tire.

“I kind of forgot momentarily that at that temperature, skin freezes in 30 seconds, never mind five minutes,” Sharpe told CTV Regina. "You might not even feel it. The frostbite came out so fast I didn't feel anything.”

Health Canada says frostbite occurs when blood vessels close to the skin constrict to protect the body’s core temperature. It makes the skin look yellowish or white, and in severe circumstances, black. Frostbite can lead to nerve damage or even the loss of limbs.

Once the damage is done, it can take years to heal. Sharpe is still going through surgeries and physical therapy 10 years later.

"It's a lifetime thing,” he said. “If you damage your hands that badly, it's for the rest of your life. You're not going to have normal hands again.”

Health Canada says homeless people, outdoor workers, seniors, infants and winter sport enthusiasts are at a particular risk for frostbite and windburn. The agency is advises anyone outside in these conditions to wear the proper clothing, including layers of synthetic and wool fabrics.

Gloves, a hat, a scarf and a warm pair of socks are also recommended. If you’re out participating in winter activities, a ski mask and goggles are also important, Health Canada says.

If you’re heading outside in frigid conditions, Health Canada also suggests avoiding alcohol, which can make you feel warm even as your body loses temperature.

People suffering from mild frostbite can be treated by reheating the body either by moving indoors and wrapping yourself in blankets, or by applying heat directly to the affected area using water that’s just above body temperature. Those suffering from severe frostbite should go directly to a doctor.

Health Canada advises against rubbing or massaging the frostbitten area, which can actually cause more damage.

With a report from CTV Regina’s Cole Davenport