Photo: University of Georgia
How important is it to know if your dial gauge canner is at the proper pressure? It is critical to the safety of any products you can in a dial gauge pressure canner.
Many local Extension offices have the ability to test specific brands of dial gauge canners. They include the brands National, Presto, Magic Seal, and Maid of Honor.
Dial gauges need to be tested yearly, and before any canning takes place. This reduces the possibility of using inaccurate pressure which could lead to underprocessed food and the potential of foodborne illness. A 1-pound error in a 20 minute process can cause a 10% decrease in sterilizing value. A 2-pound error can lead to a 30% decrease in sterilizing value. Knowing these differences can allow you to make adjustments, but it is best to replace inaccurate dial gauges.
Please note, we cannot test All American brand gauges. The manufacturer states to use the weighted gauge, not the dial gauge, to measure pressure.
Source: National Center for Home Food Preservation
