Follow the manufacturer's directions for operation of your pressure
canner before, during and following processing. Supplement these
directions with information in U.S. Department of Agriculture or
Extension publications.
Count processing time as soon as the pressure reaches 10 pounds or the
proper pressure adjusted for altitude. Be sure to hold pressure steady.
At end of the processing time, remove the canner from the heat. Allow
the canner to cool until the gage registers zero to avoid breakage of
jars and loss of liquid from jars. After a minute or two, open the
petcock gradually and remove the cover. If a weighted gage is used,
nudge the weight slightly. If no steam escapes, pressure is down. Tilt
the far side of the lid upward so steam escapes away from your hands and
face. Because food in the jars may be boiling vigorously, leave jars in
the canner about five minutes and then remove them.