The USS Robert F. Keller (DE-419) was a John C. Butler-class destroyer escort laid down on January 12, 1944, and launched on February 19, the same year. It was commissioned on June 17, 1944, under Lt. Cmdr. R. J. Toner’s command as DE-419 and served in the U.S. Navy for 21 years until it was decommissioned in January 1965. During its activities, the ship carried a complement of 215 people on board and had its main missions in San Diego, Eniwetok, Saipan, Bermuda, Okinawa, Leyte, and the West Indies. After decommissioning, the ship was struck from the Navy List on July 1, 1972, and sold for scrapping in 1974. Some highly dangerous substances - such as asbestos - used extensively by the US Navy in its World War II construction of ships - can be acutely irritating to the lungs and respiratory system, and inhalation of these substances can trigger reactions in individuals with preexisting respiratory conditions. For example, inhalation of asbestos fibers exacerbates the symptoms of COPD.