Commercial and public service announcement for the Mining Enforcement and Safety Administration; commercial begins with miner in a coal mine; male voiceover: “roof falls continue to be the major cause of fatalities in underground coal mining. Federal law will require that all mobile electric base (?) equipment be provided with substantial cabs or canopies.”; shots of test canopy structures are shown with 1000 pound and heavier weights being dropped to simulate a coal mine roof fall; statistics are quoted for lives saved by canopies on machinery, and one is interviewed: “I think they’re pretty good! I think they’re great, in my opinion of it on ‘em. It saved my life! I’ll never run another machine without a canopy!”; commercial ends with seal for the Department of the Interior’s Mining Enforcement and Safety Administration.