Dear Birck Research Community, Signs have been posted on all hoods and at the cleanroom entrance showing all UPW hoods are closed until the UPW system is repaired. We have re-opened the cleanroom for processing that doesn't require UPW and isn't sensitive to humidity control. Our UPW system parts are being ordered, so until they are installed and the UPW restored we will be running on a limited basis where no UPW process can be run and the cleanroom humidity is variable. It has been reported that the humidity in the cleanroom has recently been as low as 21%, but with warmer temperatures outside this is likely to slowly rise. Normal operating range is 40% - 50%. We will keep you updated when the UPW is restored. Ron From: BNC-all <bnc-all-bounces@ecn.purdue.edu> On Behalf Of Reger, Ronald K Sent: Monday, October 23, 2023 9:25 AM To: bnc-all@ecn.purdue.edu Subject: [BNC-all] UPW Issue Dear Birck Research Community, We had an UltraPure Water system failure on Saturday resulting in our UPW system being totally down until we can get repair parts. As a result all UPW-related processing is unavailable at this time. Additionally since UPW is used to control the humidity in the cleanroom we will have conditions where cleanroom humidity is out of range. Typically we control at 45% RH +/- 5%, and this morning it was running at 38%. So please be aware of any humidity-sensitive processes. We've closed the cleanroom temporarily this morning until signage can be placed on all UPW hoods and warning signs placed on the entrance doors. Any hoods in labs that use UPW are also closed until the UPW system can be repaired and supplying normal UPW again. We're working with the UPW parts supplier to expedite the repair parts, and we're sorry for this inconvenience. Thank you for your patience. Ron