Employee 1 was filling a forklift's propane tank. He asked Employee 2 for help to remove the hose. Employee 1 then saw a puff of white smoke and the propane tank exploded. When the tank ignited, Employee 3 was passing by to drop off or pick up material. Employees 1 and 2 sustained third-degree burns to the hands, arms, face, and ears and were hospitalized. Employee 3 sustained second-degree burns to the right arm, face, and ears. Employee 3 was treated and released.