Wind chill will not cool an object below the actual air temperature, but it will cause an object to reach air temperature more quickly than it otherwise would. Only objects that have heat in them, like the human body, are affected by wind chill. 900 to 1400 Work and recreation becomes uncomfortable unless properly clothed. Hats, coats and gloves are recommended. Outdoor work and travel are safe with quality winter clothing.
Frostbite can occur with prolonged exposure.
Heavy outer clothing is essential. Your weather office will add the current wind chill to public forecasts at this level. Frostbite can occur in a few minutes. Multiple layers of clothing become essential. 2000 or more Unprotected skin can freeze in one minute.