How long to get frostbite in -20?

The time it takes to get frostbite depends on several factors, including the individual's age, overall health, and the exposed area's clothing and insulation. However, as a general guideline, frostbite can occur within minutes at temperatures below -20°C (-4°F).

Here's a simplified estimation of frostbite development based on temperature:

- Extreme cold (below -20°C/-4°F): Frostbite can occur within minutes if exposed skin is not adequately protected.

- Very cold (between -10°C/14°F and -20°C/-4°F): Frostbite can develop in less than 30 minutes if exposed skin is not protected.

- Cold (between 0°C/32°F and -10°C/14°F): Frostbite is less likely but can still occur in several hours of exposure, especially in vulnerable areas like fingers, toes, nose, and ears.

Remember that these are estimations, and individual factors can influence the risk and speed of frostbite development. It's essential to take precautions and protect yourself against cold weather, especially when participating in outdoor activities or spending time in cold environments.