A Massachusetts Buffalo Wild Wings is under investigation after a chemical mixture inside the kitchen killed one employee and left at least 10 staff members and customers hospitalized Thursday, authorities said.
According to Patterson, the employee had been exposed to "a strong cleaning agent" while cleaning the floor of the restaurant.
The man, who was not identified, was then taken to Lahey Hospital, where he was later pronounced dead. The unidentified individual, who was an employee of the restaurant, was "suffering from nausea".
The manager was rushed to the hospital when emergency services arrived at the Buffalo Wild Wings branch in Burlington, Mass., and found him in obvious distress, Michael Patterson, assistant chief of the Burlington Fire Department, tells TIME.
According to Patterson, the cause of the freak accident was a chemical spill.
Super 8 contains sodium hypochlorite, which the Interim Fire Chief said has a "high concentrate" of chlorine and is a "common product used for floor cleaning". The worker, whose eyes instantly began to burn, fled outdoors.
Baldera, 32, worked at the restaurant as their general manager. The incident prompted a Tier 1 hazardous material response and firefighters evacuated the building.
"Is everything OK? Should we even be breathing this air?"
The restaurant will remain closed until investigators complete their work. He said it was unclear whether that substance was mixed with another chemical.
"Anyone who was in the restaurant at the time and believes they may be impacted by the incident should seek medical treatment immediately", the fire department said in a statement.
A second victim has been taken to Lowell Hospital by Armstrong Ambulance and at least nine other people who were exposed to the fumes, have driven themselves into the hospital, Patterson said.
The spokesperson did, however, send a statement the company initially released Thursday night, which said the chain is "shocked and saddened to learn of this tragic accident at our franchise-owned sports bar and are working closely with our franchisee and the authorities while they conduct an investigation".
The federal Occupational Safety and Health Administration (Osha) standards require employees to be trained in which chemicals they work with and how to use them safely. The product is commercially known as Super 8.