The investigation into that fatal lab explosion at Dow Chemical in North Andover has determined the cause of the explosion, and the identity of the victim has been released.
Carlos Amaral, 51, of Peabody, died from injuries sustained in the explosion Wednesday. He was an employee of the company and the only person in the lab when it exploded.
State Fire Marshal Stephen Coan and North Andover Fire Chief Andrew Melnikas announced Friday that the cause of the explosion was exposure of Trimethylindium, a pyrophoric chemical, to the air.
"Either there was a malfunction of the container or human error," Melnikas said.
The investigation was carried out by the North Andover Fire Department, North Andover Police detectives, State Police and the Fire Marshall's office.
At just before noon Wednesday, police received an alert of an explosion at the plant. Firefighters and EMTs rushed to the scene, where they found one employee, Amaral, covered in severe burns.
Amaral was Medflighted to Boston, where he later died from his injuries.
The explosion is also being independently investigated by OSHA, because of the workplace death that resulted from it.
According to the Fire Marshall's office, Dow did not need a permit from the North Andover Fire Department to conduct its activities. But new safety regulations created by the state Board of Fire Prevention -- implemented as a result of several chemical explosions in Massachusetts -- will take effect in January.
"I believe the chemical process safety regulations being phased in will provide better communication and coordination with the fire service and lead to improved fire safety for workers and communities," Coan said.