We're planning to move the magnets to a new building. Hoping to banish glitches we specified a "faraday cage". The architect replied: We expect that the concern will be to exclude cell phone and wireless signals, with an anticipated radio frequency attenuation requirement of between 30 and 40 dB. While 30-40 dB will probably keep cell phones out of the room, will it keep the birdies away? :) Does anyone know of a good faraday cage specification for a NMR lab? thanks, dave scott iowa state university Laugh at your problems; everybody else does.