Federal safety investigators say an engineering and construction company exposed workers to deadly hazards at the Hanwha Q Cells solar panel plant in Cartersville.

The U.S. Department of Labor’s Occupational Safety and Health Administration has cited Hyoungwon E&C America Incorporated following the death of 33-year-old Marion Jose Rugama of Norcross.

On Monday, May 19th, around 7:15 p.m., Cartersville firefighters responded to the large manufacturing facility on Great Valley Parkway at Cassville Pine Log Road. They found Rugama unresponsive on top of a storage tank, with no pulse and not breathing. A deputy coroner later pronounced him dead at the scene.

An autopsy and toxicology tests confirmed Rugama died from asphyxiation caused by a suspected nitrogen gas leak. Nitrogen, a colorless, odorless gas used in the manufacturing process, displaced oxygen in the confined space. Firefighters measured oxygen levels at just 15 percent on top of the tank — far below what’s needed to survive.

OSHA issued Hyoungwon E&C America two serious violations: one for failing to protect workers from asphyxiation hazards posed by nitrogen gas, and another for failing to provide effective training on nitrogen- and oxygen-deficient atmospheres.

The company now faces proposed penalties totaling $20,522.

The incident did not injure any other workers. It’s still unclear whether Rugama was a direct employee of Hanwha Q Cells or a contractor. However, contract labor is common at the plant.

The company has 15 business days to comply, meet with OSHA, or contest the citations. Penalties and citations can still change during the case process.