I spoke with Karen from the Lewis County Extension Office today and she was very helpful. Gauges should be checked annually by a professional/experienced gauge checker. To check Presto gauges bring the entire lid so that the ring and the gauge can be examined. If any gauge is 2-3 pounds off it needs to be replaced. New gauges run about $20. It does not mean you can 2 pounds more than the recipe calls for. At two pounds off the canning will not bring the internal temperature up high enough to kill botulism and your canned goods will not be safe. To check All American gauges just bring the gauge. If you can not get them off bring the entire lid and you will be helped.
August 14 from 11-3 you can get your gauges checked for free at Sunbirds in Chehalis. If you are local you know where that is.
August 25th the Lewis County Extension Office will be checking gauges for a nominal fee.
I suggest you go to Sunbirds if at all possible because if you need a new gauge they have them available and will save you having to send away for one. REmember if you have an older canning pot it is essential to get it checked out. Read the next entry and read the older article posted last year for more specific information.
A Master Canning class will begin on August 23rd and will run till October. If you have the time to take this class it would be wonderful and you in turn will be able to help out your community.