IBM Corporation sets all it servers and comptering rooms at a constant 70% humidity, along with a 70 Degree temperature. I try to keep my basement at tose levels. My layout is seven years now. All my electronics, locos, are in excellent operating condition. No rust, or deterioration that I can find. Some of my earlier scratch buildings/structures, in spots where paper was glued to foam board has become separated in spots. But again nothing major. And that could be from not using enough glue on the surface of some of the builds...
