A safety video about the fatal April 2, 2010, explosion and fire at the Tesoro refinery in Anacortes, Washington. The accident occurred during startup of the refinery’s “naphtha hydrotreater unit” after a maintenance shut down. A nearly 40yearold heat exchanger violently ruptured, causing an explosion and fire that fatally injured seven workers – the largest loss of life at a U.S. refinery since 2005.