Abstract: At 3:15 p.m. on January 22, 2015, Employee #1 and Coworker #1, employed by an air conditioning, heating, and refrigeration company, were working in the refrigeration room of a building under renovation. Employee #1 was operating an acetylene torch to sweat a fitting on a refrigeration unit. There were two gallon bottles of fuel to supply the torch. Employee #1 lit the torch and climbed onto a ladder when fumes in the room ignited. An explosion occurred. Emergency services were called, and Employee #1 was transported to the hospital. He was treated for third degree burns to his arms, neck, and head. Employee #1 was not hospitalized. The subsequent investigation revealed that both employees had been unaware of fumes in the refrigeration room.