I always wonder when the big tanks next to a home are recertified, or the really big tanks that are buried, when are they certified? I have had tanks for over thirty years and they are good as new. I even bought ODP valves for them and had the Farm Co-op to replace them. Recertification is a strange requirement as it does not apply to the larger tanks, I would think that the buried tanks could corrode and leak due to acid soil. I know we have to protect steel water pipes and natural gas pipes from that happening, so why not tanks?Not sure what the reasoning is behind this. If it's tank certification... that's the one time I use tank exchange. For a few bucks more than the refill price, I get a recertified cylinder that can then be refiled again once emptied.
There are reasons for the tank recertification laws and I wouldn't push a tank much past the deadline personally.