Rule 240 is a term escribing what individual airlines will do for late or stranded passengers, in the event of delays caused by airlines. The term refers to a federal requirement before airline deregulation in 1978. The major airlines have filed "conditions of carriage" with the U.S. Department of Transportation guaranteeing their respective "Rule 240" provisions. These provisions vary from airline to airline, and generally apply only to delays that are absolutely the airline's fault, such as mechanical delays, and not to "force majeure" events such as weather, strikes, or "acts of God".