Ken Goldstein is principal at Cleanroom Consultants, Inc., 13491 E. Estrella, Scottsdale, AZ 85259. He can be reached at 480-767-2400 or keng@cleanroom_consultants.com. Stephen L. Yellin is Group Director, Advanced Technology & Western Region, Lockwood Greene Engineers, Inc., 14901 Quorum Drive, Suite 900, Dallas, Texas 75254. He can be reached at 972-778-0239 or;