Danversport plants didn't follow safety rules
Blast could have been prevent, panel says
Matthew K. Roy
DANVERS -- The companies housed in the chemical plant in Danversport ignored federal and state regulations that would have prevented the Nov. 22 explosion, the U.S. Chemical Safety Board said this morning.
The plant, home to ink manufacturer CAI Inc. and paint maker Arnel Co., was also not subject to regular compliance checks by local, state and federal authorities, according to the safety board, a federal agency investigating the cause of the explosion.
Like the state fire marshal's office, the Chemical Safety Board identified a mixture of flammable chemicals as the fuel source behind the explosion. That mixture was overheated, vapors filled the plant and an unknown spark triggered the explosion.
But the explosion could have been avoided if the plant's ventilation system had not been shut down at night, a violation of the federal Occupational Safety and Health Administration's guidelines for handling volatile chemicals.
"We determined that it was routine practice to turn off the ventilation system at this facility during the overnight hours," said John Vorderbrueggen, the lead investigator for the Chemical Safety Board. "This unsafe practice allowed flammable vapor to accumulate inside the building and was the immediate cause of the explosion."
The fire marshal cited human error -- a worker failed to shut off a steam-heat system warming the chemicals -- but safety board investigators reported that a worker claimed to have turned off the heat. The explosion destroyed the heating system and no evidence was left over to draw any conclusions.
"We investigate many accidents every year and it isn't that this event occurred, it's the amazement that it hasn't occurred sooner," Chemical Safety Board Chairman Carolyn Merritt said. "When you have a system where there are no automatic shut downs and everything is manual, human error can occur."
"They did not have any safety systems," Vorderbrueggen said. "It was a very basic operating system."
Massachusetts fire regulations mandate that, when large quantities of flammable liquids are stored inside a building, the tanks must be vented to the building's exterior.
"Tank piping must have approved, automatic shutoff valves, and the piping must be made of fire-resistant material or protected from fire exposure. Our team concluded that these important safeguards were not in place at CAI-Arnel," Vorderbrueggen said.
The companies also did not have the required permits to handle volatile chemicals, including heptane and propyl alcohol, the fuel for the blast.
The last time any local, state, or federal authority was inside the plant was 2002, when the Danvers Fire Department consulted one of the companies installing a fire suppression system.
The Chemical Safety Board ruled out natural gas as a cause for the explosion, a suspicion of many residents of Danversport.
"We found no evidence of any leak of a magnitude that could cause this kind of problem," Investigator Robert Hall said. "Additionally, we found no credible pathway that natural gas could get into the building."
Danvers: John Vorderbrueggen, of the U.S. Chemical Safety and Hazard investigation Board, lead investigator, speaks to the press about the CAI explosion, that occured on November 22, 2006 in Danversport. Mark Lorenz/Staff Photo(Click for larger image)