Sprinkler,
I do not think that steel tubes on the ceiling for sprinkler heads
will affect the magnet to any extend.
But: Do not install sprinkler heads directly above a magnet. They
have been known to go off in case of a quench. The heads can freeze
quickly in the cold helium, and then sprinkle. Beware.
Cheers
Rolf Tschudin Tel. 301 496 2692
Contractor, NMR Systems Fax. 301 496 0825
National Institutes of Health
9000 Rockville Pike
Bldg. 5, Rm. B2-41
Bethesda MD 20892
USA
Received on Fri Oct 11 2013 - 09:40:28 MST