How long does it take to get frostbite?
Out in the cold? Signs of frostbite can begin in as little as 30 minutes. Find out how to keep your family safe this season.
It’s beginning to look a lot like … winter! Frigid temperatures, snow flurries and blustery winds make for great skiing, snowmobiling or ice skating. But while walking in a winter wonderland can be fun, exposure to extreme cold and wet conditions can go from uncomfortable to dangerous in minutes.
Frostbite is a serious cold-weather injury that occurs when skin and underlying body tissues freeze. It typically affects the fingers, toes, ears, nose, cheeks and lips. And if it’s not treated quickly, it can cause severe complications and even permanent damage.
“Kids can be at greater risk for frostbite because they lose body heat from their skin faster than an adult,” says Lindsey Duguet, DO, an emergency medicine provider at Geisinger. “Plus, they don’t want to stop their fun in the snow to come inside to warm up.”
Frostbite symptoms
If you’re out in the cold too long, your skin may become cold, red and painful. These are the first signs of frostbite, and a warning to cover exposed skin and get out of the cold quickly.
Other signs of frostbite can include:
- Tingling or numbness
- Discoloration, such as red, white or gray-yellow skin
- Blistering and swelling
- Tissue that is unusually firm or waxy
- Joint or muscle stiffness
How long does it take to get frostbite?
In general, frostbite can occur in as little as 30 minutes in frigid conditions with wind chills below –15° F.
When symptoms start to set in depends on many factors, such as wind chill, air temperature, amount of exposure and whether you’re dressed properly.
According to the National Weather Service’s Wind Chill Chart, if it’s 5° F outside with a wind speed at 35 mph, frostbite can occur after about 30 minutes. But if the temperature drops to –5° F at that same wind speed, frostbite can set in after about 10 minutes.
“A person’s skin cools down quicker when there’s more wind,” explains Dr. Duguet. “As the wind blows over your body, it causes sweat to evaporate from your skin, cooling you down.”
Stages of frostbite
Frostbite happens in three stages. Knowing them will help you determine the best treatment — and prevent further damage.
Frostnip
Frostnip is a milder form of frostbite. Typically, it’s reversible by rewarming the skin at home and doesn’t cause permanent damage. With frostnip, you may notice some tingling and numbness in the area.
Superficial (surface) frostbite
Superficial frostbite is more serious than frostnip. You may notice red or white patches on your skin, and once you rewarm the area, you may feel stinging, burning and even some swelling or skin peeling. Blisters can appear up to 36 hours after rewarming the skin.
Deep frostbite
Deep frostbite is the most severe form and affects all layers of the skin, including the deeper tissues. It can cause permanent damage to the skin, tendons, muscles, nerves and bones. As total numbness sets in, your skin may turn white or gray initially. As the skin dies, it can turn black and hard.
Frostbite treatments
Treatment depends on the stage of frostbite. If you think you have frostnip, get out of the cold immediately and slowly rewarm the affected areas. Remove any wet clothing and use warm water or body heat until sensation returns.
“Don’t use hot water, heating pads or other heat sources,” advises Dr. Duguet. “If your skin is numb, you won’t be able to feel the heat and can get severely burned.”
If sensation doesn’t return after a few minutes or symptoms get worse, seek immediate medical attention. Superficial and deep frostbite are considered a medical emergency that should be treated promptly to prevent further damage.
Frostbite prevention
Frostbite is dangerous because it often numbs your skin so you may not feel that anything’s wrong.
Dr. Duguet offers four tips to help prevent frostbite this season:
- Stay updated on weather forecasts. If it’s calling for freezing temperatures and wind chills, avoid the outdoors as much as possible. Even brief exposure to frigid weather can cause frostbite.
- Cover all exposed areas. If you must go out, dress in warm layers and cover all exposed body parts with a winter hat, gloves and a scarf. Choose inner clothing layers that absorb moisture and outer layers that are windproof and waterproof. Also, wear warm and waterproof boots.
- Take regular breaks from the cold. If you need to be outside for extended periods, come inside about every 15 minutes to warm up and hydrate — and check for signs of frostbite.
- Change wet clothes or shoes immediately. Wetness can speed up the process of frostbite because wet clothes draw heat away from the body.
“Prevention is the best defense against the harsh elements,” says Dr. Duguet. “Dressing in plenty of warm layers and using a little common sense can go a long way in preventing frostbite this winter.”
Next steps:
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