A nuclear safety engineer, Lochbaum is one of the nation's top independent experts on nuclear power. He joined the staff of the Union of Concerned Scientists in 1996 and directs the organization's Nuclear Safety Project. He monitors safety issues at US nuclear power plants, raises concerns with the Nuclear Regulatory Commission, and responds to breaking events such as the 2011 nuclear reactor crisis in Japan. His expertise is in nuclear power plant design, nuclear regulatory oversight, and nuclear waste issues. Lochbaum worked in nuclear power plants for 17 years.