Abstract: At approximately 3:30 p.m. on December 5, 2011 , a Mechanical Equipment Systems Apprentice, was performing brazing operations within the Bakery Department's walk-in cooler. The employee was conducting a bridge repair of the refrigeration unit's evaporator coil using a copper topper and a silver alloy. The employee had been sent to this site by the employer to perform brazing operations on a hole in the evaporator coil that had been leaking inside of the bakery's cooler. The employee had been on-site for approximately one hour when he walked outside telling another employee, the site leader, that he was going to get some fresh air. He exited the side door of the store where he was found approximately 10 minutes later, directly outside of the door, unresponsive. The employee had a myocardial infarction and died.