VERGENNES — According to a United Technologies Corp. spokesperson this week the company has taken steps to prevent a recurrence of the Dec. 8 explosion that injured four UTC employees at its Panton Road plant in Vergennes, but the exact cause of the event remains under investigation.
As was quickly determined, the explosion shortly before noon that Friday occurred in a dust collector on the outside of the building, one that works in tandem with an interior sanding machine. A witness reported that a portion of the roof of the Panton Road plant was damaged, and there was a fire.
UTC spokesperson Annie Donnelly reconfirmed the source of the event.
“The explosion at the Vergennes facility occurred in the dust collection system used to exhaust aluminum dust from a sanding machine. The sanding machine is used in the production of aircraft sensors manufactured in Vergennes,” Donnelly wrote in an email.
Despite rampant local speculation about the incident, Donnelly said UTC had not pinned down the cause. The Vermont State Police investigator working on the case did not respond to an email sent on Monday before the Wednesday deadline for this newspaper; that email sought the status of the probe from the VSP point of view.
“At this time, the investigation is still ongoing,” Donnelly wrote. “We expect it will be completed in January.”
Donnelly said after the incident UTC stopped using not only the sander and exhaust system, but also similar equipment.
“The sanding machine, its associated exhaust system, and any similar systems have been removed from service and are being evaluated to ensure that they are safe for use,” she wrote. “Our primary focus remains the safety of all our employees while providing support to those impacted by this incident.”
After the explosion four workers were hospitalized, although three were released later that evening. Donnelly said all four remain off the job.
“The employees who received treatment at the hospital have all been released and are at home recovering,” she wrote. “We are regularly monitoring their progress and remain committed to providing them with support during their recovery from this unfortunate event. We also want to reiterate our thanks to all the first responders for their support.”
The Vergennes Sensors and Integrated Systems plant on Panton Road employs 775 people. UTC makes equipment for the aerospace and defense industry.
Key products made in Vergennes over the years have included Health and Usage Monitoring Systems (HUMS) for military helicopters. HUMS are designed to measure wear and tear on helicopters’ operating systems to predict accurately when maintenance should be performed, thus enhancing passenger safety and preventing unnecessary expenses.
In 2014, UTC won a $6.7 million Department of Defense contract to develop and test improved guidance systems for U.S. munitions, which would allow greater precision and avoid damage to innocent bystanders and property.
The contract with the Defense Ordnance Technology Consortium was for developing and testing of low-cost Guidance, Navigation, Control and Targeting (GNC&T) systems for precision munitions, which was developed at the Vergennes facility.