An OSHA investigation found several safety violations contributed to the accident at the McDonald's restaurant on U.S. Highway 17-92 in Sanford.

OSHA fined NuCO2 of Stuart $12,600 and McDonald's franchisee 3BM Casselberry Inc. $21,150. Both companies are contesting the penalties.

George Torres, a driver for NuCO2, and Christopher Edgar, a McDonald's employee, were suffocated by carbon dioxide Jan. 8 as Torres tried to deliver the gas, which is used to carbonate sodas. Edgar was helping to transfer the compressed gas from a NuCO2 delivery truck parked behind the restaurant.

Police investigators think Torres took the supply hose through an emergency door, but the hose could not reach a fill valve in an adjacent storeroom because the door was locked, according to the Sentinel.

Edgar, 18, scaled a 10-foot wall into the storeroom, which had no ceiling, to open the door from the inside, but it had a deadbolt lock that required a key. Torres fed the hose over the wall to Edgar, but Edgar was overcome by the gas. Torres, 49, then apparently climbed over the wall and was also overcome.

The OSHA investigation found the McDonald's failed to provide a safe work environment because Edgar had to use a six-foot ladder to scale the 10-foot wall, and the only exit to the storage area required a key. The McDonald's also did not provide information on-site for handling the hazardous gas and failed to inform or train its employees about the hazards of carbon dioxide.

NuCO2 was cited for allowing an employee to be exposed to dangerous concentrations of carbon dioxide and for having no procedure to inform the McDonald's franchise how to recognize and protect employees from an accidental gas leak.