The cause of an explosion and subsequent fire at a Woburn company Tuesday was identified Thursday as a static electrical charge by State Fire Marshal Stephen D. Coan’s office.
The explosion occurred at the Powderpart company on Wildwood Avenue when an employee was using a vacuum to clean up machinery. The vacuum was improperly grounded, which caused a build-up of static charge, igniting dust that caused the explosion, Coan’s office said in a statement Thursday.
The employee using the vacuum was critically injured. A worker from a neighboring business who tried to assist the man sustained minor injuries. A police officer also suffered minor injuries because of smoke inhalation, the fire marshal’s office said.
The regional Hazardous Materials Response Team responded to the scene and deenergized the vacuum, monitoring the area until it was safe for investigators to enter.
Powderpart specializes in 3-D printing for medical and aerospace applications, according to its Twitter profile. The company uses metal powders and 3-D printing that involves lasers, Coan’s office said.
The explosion was investigated by Coan’s office, the Woburn Fire Department, State Police, Department of Fire Services Code Compliance officers, and the federal Occupational Safety and Health Administration.