The BNC Cleanroom and all chemical processing in the BNC laboratories will be shut down TOMORROW, 22 May 2013, from 7:30-9:30 AM. NO CHEMICAL PROCESSING WILL BE ALLOWED IN THE BNC - and the cleanroom will be closed - during this period. All systems are expected to return to normal operation by 9:30 AM. This shutdown is necessary to replace a defective valve in the tempered water system that supplies all of the safety showers in the building. My apologies for the short notice, but this is a sudden problem that must be fixed as soon as possible. John John R. Weaver Facility Manager Birck Nanotechnology Center Purdue University (765) 494-5494 jrweaver@purdue.edu