HALL COUNTY, Ga. - Officials released the cause of death for the six people killed in a Hall County food processing plant on Jan. 28 on Friday as firefighters were call back to the plant for another incident.
Hall County Sheriff’s investigators said the cause of death for all six victims was asphyxia due to, or as a consequence of liquid nitrogen exposure. That from the results of the autopsies conducted by the Georgia Bureau of Investigation Crime Lab.
Officials said 45-year-old Jose DeJesus Elias-Cabrera, 35-year-old Corey Alan Murphy, 28-year-old Nelly Perez-Rafael, 41-year-old Saulo Suarez-Bernal, 38-year-old Victor Vellez, and 28-year-old Edgar Vera-Garcia died in the Foundation Food Group plant located off Memorial Drive.
Nine other workers were sent to the hospital and later released, including one who was hospitalized for weeks.
Hall County Fire said there was a leak of liquid nitrogen at the facility. Poultry plants rely on refrigeration systems that can include liquid nitrogen. Several federal, state, and local agencies were investigating the incident including the Hall County Sheriff's Office, the U.S. Occupational Safety and Health Administration, the U.S. Chemical Safety and Hazard Investigation Board, and the state fire marshal.
The liquid nitrogen system was installed to replace an older refrigeration system that used ammonia, the Chemical Safety Board said.
When leaked into the air, liquid nitrogen vaporizes into an odorless gas that’s capable of displacing oxygen. That means leaks in enclosed spaces can become deadly by pushing away breathable air, according to the U.S. Chemical Safety Board.
The company resumed operations at the plant weeks later.
The Associated Press reports a refrigeration company and firefighters were called back out to the plant on Friday afternoon. Hall County firefighters said they were called to the plant about 4 p.m. Thursday concerning an ammonia leak that may have happened around 9:30 a.m.
"Hall County Fire Services has responded to the location, evaluated the scene, and found no hazards, including ammonia, to be present," Division Chief Zach Brackett wrote in an email.
It’s unclear if there was an ammonia release earlier. The company released a statement but didn’t respond to specific questions.
"After a review of the Foundation Food Group prepared foods facility today by a professional refrigeration company, no actionable levels of ammonia were found, and the plant was cleared of any potential risk to the company’s employees," the statement said in part.
It’s unclear whether Thursday’s concerns centered on the same production line where January’s release occurred or was somewhere else in the plant.
Eric Lucero, a spokesperson for the Occupational Safety and Health Administration, said the workplace safety agency "has been provided limited information," but is "actively looking into the circumstances surrounding the event." The Chemical Safety Board did not respond to questions.
Neither agency has yet released findings from investigations of the January liquid nitrogen release.
Families of a number of dead workers have filed lawsuits against the German company that made the liquid nitrogen system, Messer Group, and a Messer employee who visited the plant in the days before the leak to service the system. Those suits allege Messer and the worker are at fault for failing to properly inspect, test, repair or shut down the system before the liquid nitrogen release.
The plant takes chicken slaughtered elsewhere and prepares items such as patties and nuggets for food service operations.
Gainesville is the hub of Georgia’s poultry industry, which is the largest in the country. Thousands of employees work across multiple processing plants around the city.
The Associated Press contributed to this report
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