Read the report and updated coverage.Phosgene plant could have left plant, crossed river, CSB says CHARLESTON, W.Va. -- DuPont Co. rejected affordable plant and equipment upgrades, ignored near-miss incidents and violated the chemical giant's own widely touted safety guidelines in failing to prevent three January 2010 accidents that left one Belle plant worker dead, federal investigators said in a report issued Thursday.U.S. Chemical Safety Board officials found common threads -- including poor maintenance practices, ineffective warning alarms, and insufficient accident investigations -- among the three incidents that occurred over a 33-hour period Jan. 22-23, 2010.Chief among the findings was that nearly 25 years ago DuPont rejected proposals to enclose the Belle plant's phosgene unit, a move that would have protected workers and local residents from the poisonous material used as a chemical weapon in World War I.CSB investigators also concluded that the most serious of the incidents, a fatal phosgene leak, was caused by the use of the wrong type of chemical hose and DuPont's failure to replace even that inadequate hose on its own required schedule."These kinds of findings would cause us great concern in any chemical plant -- but particularly in DuPont with its historically strong work and safety culture," said CSB member John Bresland, a longtime chemical plant manager and one-time DuPont lab technician. "In light of this, I would hope that DuPont officials are examining the safety culture company-wide."Board Chairman Rafael Moure-Eraso said, "Tragedies can occur even with companies with highly-regarded safety cultures" and urged Kanawha Valley and West Virginia officials to create a local chemical plant accident prevention program.DuPont officials said that they are reviewing the CSB report, but had already taken a variety of steps to improve safety procedures based on their own internal review of the incidents. "Safety is a core value at DuPont and is our most important priority," company spokesman Dave Hastings said. "Our goal is zero -- meaning we believe all incidents and injuries are preventable."In their 172-page report, CSB investigators focused on the Jan. 23, 2010, phosgene leak that killed plant worker Danny Fish. Agency experts also examined a methyl chloride leak that went on for five days before being discovered on Jan. 22, 2010, and a release of the chemical oleum the same morning as the deadly phosgene leak.The report was issued in draft form. It won't be finalized until after a 45-day comment period that ends Aug. 22 and until the board approves the final version.CSB officials found that the methyl chloride leak occurred when excess pressure caused a "rupture disc" to burst as designed to relieve that pressure. But 2,000 pounds of toxic methyl chloride was released before the leak was stopped five days later. An alarm system on the rupture disc was so unreliable that it went off routinely, leading workers to ignore the leak warnings. The problem had come up before, but DuPont had never fixed it, CSB investigators found.In the oleum incident, corrosion under the insulation caused a leak. DuPont officials knew this could be a problem on the piping in question, but did not include that part of the plant in an improved preventative maintenance plan, according to the CSB.Board experts blamed the fatal phosgene leak on a worn-out Teflon and braided-steel hose. The hose had been in service for more than seven months, but was supposed to be replaced after 30 to 60 days. The hose ruptured and sprayed Fish in the face with liquid phosgene while he was checking the chemical level in a one-ton phosgene cylinder."DuPont did not follow its own standards for the change out of phosgene transfer hoses," the board's report concluded.DuPont officials also ignored their own experts' concerns that the type of hose used was not safe for a material as toxic as phosgene, and never followed through on recommendations for reconstructing the entire phosgene area of the plant to make it safer, the CSB found.CSB investigators uncovered internal DuPont documents that detailed the company's consideration in 1988 of the proposal to totally enclose the phosgene area. A company study determined the proposal would be safer, and was affordable at a cost of $2 million.But the plan was dropped after one employee -- whose name was not made public -- questioned whether the project "sets a precedent for all highly toxic material activities."Company experts have recommended similar enclosures several times since that 1988 memo, but such projects have repeatedly been delayed, the CSB reported.In their report, board investigators said, "an enclosure, scrubber system, and routine requirement for protective breathing equipment before personnel entered the enclosure would have prevented any personnel exposures or injuries."While highly toxic, phosgene is a valuable building block for making other chemicals. At Belle, DuPont was buying one-ton cylinders of phosgene and using the chemical to make intermediates, which were then used to make crop-protection products.The DuPont phosgene unit has been out of operation for business reasons since the January 2010 incident, and CSB officials urged the company not to restart it unless they build the enclosure.Belle plant manager Jim O'Connor said DuPont has no plans to resume using phosgene at the plant.Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.