MARIETTA, Ga. -- A man found dead inside of a walk-in cooler at SunTrust Park died from his own beer equipment, according to autopsy results released by officials on Thursday.
On the afternoon of June 26, workers found 48-year-old Marvin Todd Keeling inside the beer cooler at the ballpark.
According to information released by Cobb County officials on Thursday, autopsy results indicated that Keeling died of "asphyxia due to carbon dioxide exposure."
Investigators found images on Keeling's cell phone that indicated he went into the cooler to work on the valve system.
Officials and family previously told 11Alive that Keeling was working to install a new patented beer tap -- one he invented that dispensed beer faster and with less foam – at the ballpark before he died.
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Carbon dioxide is used to provide carbonation in beer tap systems, Cobb officials said.
Investigators couldn't determine when Keeling went into the cooler or how long the cooler had been closed before he entered.
Cobb County firefighters found that the concentration of carbon dioxide increased quickly after they turned on Keeling's equipment.
Investigators also found that the door handle to the cooler malfunctioned, which might have prevented a quick escape, Cobb officials said. Investigators said there was no evidence Keeling tried to use that door, or that he used the cell phone he had with him.
According to the report, Keeling likely became "so disoriented he was unable to form and act on logical thought processes."
The autopsy ruled the death an accident, and no charges will be filed, according to Cobb County Police.
Keeling had installed the device at two other Major League Baseball parks before his death, according to his family.
