ACHIM WECHSUNG, PhD, P.E., is a senior engineer in the Thermal Sciences practice at Exponent, Inc. (1075 Worcester Rd, Natick, MA 01760; Email: awechsung@exponent.com). He consults primarily in the areas of hydrogen, petrochemical, chemical and industrial processing, oil and gas, process safety, risk analysis, fire and explosions, and advanced modeling. He has investigated incidents at petroleum refineries, chemical, and industrial processing plants, as well as fires and explosions at residential and industrial sites. In addition, he is also a principal member on the technical committee for NFPA 2, “Hydrogen Technologies Code,” and a member of CIGRE Joint Working Group C5/C1.35 “Integration of hydrogen in electricity markets and sector regulation.” Prior to joining Exponent, he worked as an engineer for one of the largest chemical companies. He holds a Dipl.-Ing. degree in mechanical engineering from RWTH Aachen Univ. and a PhD in chemical engineering from the Massachusetts Institute of Technology. He is a licensed PE in chemical engineering in California and a Certified Fire and Explosion Investigator.