Five employees were working in the maintenance shop of a pyrotechnic facility consisting of 2 bunkers used to store explosives, three production buildings, one mixing building, a maintenance shop, and an office trailer. The bunkers, production buildings, and mixing building were constructed of concrete blocks. The product being manufactured was a rocket motor consisting of a 7 cm by 1.5 cm cardboard cylinder containing black powder, with a clay cap at each end. They were use to propel the toy rockets and were ignited by lighting cords that were inserted in the nozzle end of the motor. The basic manufacturing process at this facility consisted of removing the black powder from the bunkers, blending it with water and alcohol in the mixing building, and using index machines in the production building to compress the black powder explosive into a cardboard cylinder. The indexing machines also placed the clay cap at each end of the cylinder. Workers often used pneumatic drills, mounted in small presses, to drill black powder out of the nozzle end of the motor to make the correct shape to insert the igniter cord and to ensure proper rocket motor propulsion. This rework operation, called motor drilling or kiss drilling, was normally done in the mixing building. At approximately 11:40 a.m., a flash fire occurred in the maintenance shop, killing 4 and injuring 1 (burns). The material of the coveralls worn by the workers may have contributed to their injuries. Damage was estimated at 20,000 $. The company was fined by OSHA for violations of workers safety standards.