Attachment 1 - BUILDING 215 - Basis of Design Report.pdf

This is a Basis of Design Report for the National Institute of Standards and Technology (NIST) Building 215 Cleanroom Re-Balance project, prepared by Burdette, Koehler, Murphy and Associates, Inc. (BKM) as a 35% design submission dated December 6, 2019.

The report documents existing conditions and provides comprehensive recommendations for correcting deficiencies in the Advanced Measurement Laboratory (AML) Building 215's air handling systems at NIST's Gaithersburg, Maryland facility. The facility contains 1,800 square meters of cleanroom space, including 750 square meters of Class 100 space, operating with approximately 120 air changes per hour for Class 1000 areas and 300 air changes per hour for Class 100 areas. Key deficiencies identified include original HEPA filters (installed in 2005) requiring replacement due to increased pressure drops; malfunctioning variable air volume (VAV) terminal units and airflow measuring stations (Ebtron AFMs) providing inaccurate readings; undersized and poorly balanced exhaust ductwork that has been modified to accommodate newly installed equipment; inadequate return air pathways causing pressurization issues; and magnehelic gauges with incorrect operating ranges. Primary recommendations include replacing HEPA filters and AFMs, repairing or replacing VAV terminals and magnehelic gauges, correcting ductwork pathways, installing volume dampers on exhaust systems, rebalancing all cleanroom and support space air handling units and exhaust fans, addressing return air pathways to eliminate wind tunnel effects in corridors, and implementing differential pressure monitoring sensors. The scope encompasses multiple air handling units (AHU-101A through 115), exhaust fans (EF-101 through EF-123), and support systems including testing, calibration, and full commissioning services to restore the cleanroom to proper operational specifications.