On June 11, 2003, an explosion occurred in the natural gas-fired ethyl benzene reboiler at a styrene plant in Bayport, Texas. The incident occurred while the air damper and registers were being adjusted to stabilize the flame and the excess oxygen content of the stack discharge. Following the rupture of the heater housing, fire erupted in the radiant section and the inlet header. The fire burned for three-and-one-half hours as ethyl benzene continued to feed the fire from return piping connected to the ethyl benzene column. The reboiler was completely destroyed. This article summarizes how it was determined what evidence to collect; how initial evidence was collected soon after the incident; how the physical evidence was preserved during the "make safe" and demolition stages; and how evidence was staged and protected after demolition. (c) 2006 American Institute of Chemical Engineers Process.