In most home canning recipes, recommended processing times for boiling water canners are given for elevations of 0 – 1000 ft. (sea level – 305 m). When using a boiling water canner at altitudes higher than 1000 ft. (305 m), sterilizing and processing times must be extended. Air is thinner at higher elevations, so water boils at temperatures lower than 212°F (100°C). These lower temperatures are less effective in destroying microorganisms, therefore, increased processing times are necessary to ensure the safety of home canned foods preserved at higher altitudes.
The processing times given on this website are for Alberta altitudes of 1001 – 3000 ft. (305 – 914 m). For higher altitudes of 3001 – 6000 ft. (915 – 1829 m), add 5 minutes to sterilizing time for jars and to processing times shown unless stated otherwise.