Mohinder L. Nayyar, P.E., ASME Fellow, is Senior Engineering Specialist for piping and valves in the engineering department of the Bechtel Power Corporation in Frederick, Maryland, and the Editor-in-Chief and an author of the sixth and seventh editions of the field-leading Piping Handbook. As a Bechtel consultant, he has assisted many leading companies, and has supervised and supported both nuclear- and fossil-fueled projects around the world. He is Chairman of the Materials Technical Committee of the ASME B31, Pressure Piping Code, and of Materials Group of ASME B31.1, Power Piping Code; a member of ASME B16 Main Committee; and several other standards committees. He lives in Brookeville,… Maryland.