For your awareness. From: Harlan, Richard D <rharlan@purdue.edu> Sent: Wednesday, August 12, 2020 3:17 PM To: bnc-facility-notice@ecn.purdue.edu Subject: Upcoming PM on Argon & Oxygen Tanks Dear Birck Research Community, This is a reminder the preventative maintenance on the Praxair Argon and Oxygen microbulk systems will occur tomorrow, 8/13/20, between 8:00am and 5:00pm. We ask that all users limit the use of Argon or Oxygen while this PM work is performed. Thank you for your support, Birck Staff Original message sent Friday, 8/7/20; Our Staff is working to maintain a safe environment while meeting all of our user's needs in the Birck Nanotechnology Center and we wanted to make you aware of an upcoming preventive maintenance activity on two of our process gas tanks. Our Praxair Argon and Oxygen microbulk systems are in need of this preventive maintenance service and the work will be performed by Praxair. It is expected to only take a few hours to complete and we will have external cylinders on-line to provide continuous pressure and flow of Ultra High Purity (UHP) Argon and Oxygen while the work is being done. Planned Work The Praxair service engineer will be replacing the pressure relief safety valve which prevents the gas vessel from exceeding the permissible vessel pressure. During this work he will also add a valve that will allow future work to occur without disrupting our gas supply, or the need to connect external supply cylinders. The back-up UHP gas cylinders will be put on-line by Cryogenic Systems personnel prior to the Praxair work so the Birck facility will have continuous service. However, we ask that no work be performed that will use higher than normal amounts of Argon or Oxygen while this PM work is performed. Date of Work This work is planned for either Thursday, 8/13/20, or Friday, 8/14/20, depending on when the microbulk tanks can be filled. The work will occur between 8:00am and 5:00pm, and once the schedule is finalized we will notify the user community again. Thanks for your support for this important maintenance item. Birck Staff