You always bring something that have some history behind.
The plant does not look very old, many of items still look fresh to date. It seems that it was built to produce tons of aluminum products, Pechiney is now part of Alcan a Canadian giant.
You were very lucky to see the cause of building fire, I think insurance company had not paid them any compensation against the claims regarding devastation done by that fire breakouts.
I'll reconsider buying Mercury alarms lol.
Considering its been empty for over a decade, it is in remarkably good condition. It could be that security have been there for years and only recently stopped being paid.