Buffalo, NY – DuPont engineers overlooked a hazard that led to an explosion that killed one contract worker and injured another, concludes a new report from the Chemical Safety Board.
The final report (.pdf file), released April 19, is accompanied by a safety video depicting the November 2010 incident at the DuPont chemical plant in Tonawanda, NY.
The explosion was triggered by sparks or heat from welding that occurred on top of a process tank filled with flammable vinyl fluoride, according to CSB. The investigation found that DuPont workers monitored the atmosphere above the tank but failed to check for flammable vapor inside the tank.
Additionally, CSB said DuPont incorrectly assumed vinyl fluoride could not reach flammable levels inside the tank and did not properly isolate and lock out the tanks, which allowed the vapor to pass from a different tank and into the tank that was being welded.
CSB researchers recommend monitoring the atmosphere inside and around tanks before performing hot work, which is defined as welding, cutting, grinding or other spark-producing activities.