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Nov 20, 2003

U.S. Chemical Safety Board to Conduct Full Investigation of DPC Enterprises Chlorine Leak in Glendale, Arizona

Washington, D.C., Nov. 20, 2003) The U.S. Chemical Safety and Hazard Investigation Board (CSB) announced today it will extend to a full investigation its inquiry into the chlorine release which occurred at the DPC Enterprises facility in Glendale, Arizona (near Phoenix) last Monday, Nov. 17.

Board Member John Bresland, accompanying the investigation team in Phoenix, said, "Our preliminary investigation has indicated a need to investigate further the immediate and root causes of the chlorine release. Chlorine is a highly toxic chemical used in a wide range of chemical processes throughout the United States, and we want to see what lessons can be learned from this accident to prevent releases in the future."

The release, which caused authorities to evacuate citizens from the immediate area and close neighboring streets for hours, occurred as chlorine was being transferred from a railroad tank car to a tanker truck. Excess vapor in the process was being vented to a "scrubber," an environmental control device designed to prevent chlorine from escaping into the air. The scrubber failed to function properly and allowed chlorine gas to escape. Authorities said 14 people, including 10 Glendale police officers, were treated for chlorine-related symptoms, including nausea, throat irritation, and headaches.

Mr. Bresland and the CSB investigation team, headed by lead investigator John Murphy and including Michael Morris, has examined the offloading process at the chlorine repackaging plant, and interviewed workers, operators, and plant managers. They have been gathering information from local police and fire departments concerning community notification and emergency response. The team has requested documents relevant to DPC's process at Glendale, and will be consulting the Chlorine Institute (the industry's main trade association) and other companies that manufacture or process chlorine on safety practices in chlorine handling.

Testing will be performed on the emergency shutdown valves attached to the rail and tank trucks and on the equipment used in the scrubber system that is supposed to prevent overloading and warn operators of impending failure and the potential for a chlorine release.

Mr. Bresland said the team would return to Washington Friday and begin piecing together information from the interviews, testing, and other data.

The CSB completed an investigation in May of this year on a massive chlorine leak at a DPC Enterprises facility south of St. Louis, which occurred Aug. 14, 2002.

Further information about the earlier DPC incident is available at under "Completed Investigations."

The CSB is an independent federal agency charged with investigating industrial chemical accidents. CSB investigations look into all aspects of such events, including physical causes such as equipment failure as well as inadequacies in safety management systems. Typically, the investigations involve extensive witness interviews, examination of physical evidence, and chemical and forensic testing.

The Board does not issue citations or fines but does make safety recommendations to plants, industry organizations, labor groups, and regulatory agencies such as OSHA and EPA. Further information about the CSB is available from

For more information, call Sandy Gilmour Communications, 202-261-7614 CELL: 202-251-5496 or Daniel Horowitz, 202.261.7613 CELL 202.441.6074

Media Coordinator in Phoenix: SGC Associate Dana Weidaw, 480.361.8104 CELL 602.402.2200



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