I am not worried about the one piece aluminum 2 oz tins. The square and rectangular tins are a concern. Best I came up with is to store all the tins in airtight containers. The barn is also temperature and humidity controlled, like all barns are. Not saying I cant have an issue, but I am taking what precautions I can. I am also looking to hire someone to inspect the tins for rust on a regular basis, but that is the subject of another thread to come.