As long as tubes aren't used and don't have a vacuum leak they should last forever. In time I expect all tubes lose vacuum but it might take centuries. How they are stored isn't going to make a difference.
Norm
:Hello guys...there has been a lot of talk about tubes and storing them. What I was wondering, at what point does a tube not work from sitting in storage for 50 years. I have been storing mine in water tight rubbermaid totes over the years, but most of there life they have been in a cardboard box in someones basement or attic. Will they last another 50 years?????
:Thanks
:David
Thomas