By Matthew Chin

David Okrent, UCLA professor emeritus of mechanical and aerospace engineering, who made pioneering contributions in nuclear reactor design and safety, died Friday, Dec. 14. He was 90.

Okrent received his bachelor’s degree from Stevens Institute of Technology in 1943. He then attended Harvard University for graduate school and received his Ph.D. in 1951, with his dissertation titled, “On the Sensitivity of Photographic Grains to Electrons.”

After receiving his Ph.D., Okrent joined Argonne National Laboratory in Illinois, starting out as an associate physicist. He quickly rose through the ranks and became the manager of the lab’s Fast Reactor Physics and Safety in 1957, a position he held through 1971.

After spending 20 years at Argonne National Lab, Okrent joined UCLA Engineering as a faculty member and established a world-leading research program in nuclear safety. Okrent taught undergraduate classes in thermodynamics, nuclear reactor theory and design, and probabilistic risk assessment, and he led graduate-level courses in several areas of reactor safety and design. During his tenure he advised 50 Ph.D. students.

“David did not believe in giving a prescription to research, and, instead, he always answered questions with great questions of his own,” said Vijay Dhir, dean of the UCLA Henry Samueli School of Engineering and Applied Science, who considered Okrent a mentor, a longtime collaborator and close friend. “He was a brilliant scholar, a great thinker, a superb mentor of graduate students and, above all, he was a true gentleman. His influence spread far and wide in establishing a culture of safety for nuclear reactors.”

Throughout his career, Okrent received many prestigious honors for his work, including a Guggenheim Fellowship. In 1974, Okrent was elected to the National Academy of Engineering for “contributions in fast reactor design, including critical experiments, safety tests and analyses, and neutron cross-section evaluation.

In 2007, Okrent was honored by the American Nuclear Society with its George C. Laurence Pioneering Award. It recognizes individuals who have made outstanding pioneering contributions to the field of nuclear reactor safety over their lifetime.

Okrent retired from UCLA in 1991, but continued teaching classes and mentoring graduate students for several years after that.

Memorial services for Okrent were held on Dec. 17 at Hillside Memorial Park and Mortuary in Los Angeles.