In Germany, Alstom produces regional trains, trams, rapid-transit and underground trains as well as engines. Before approval for active service by the German Federal Railway Authority, every train must pass a host of tests under diverse real-world conditions to prevent derailing and ensure overall safety and riding comfort.According to the Association of American Railroads, if 25% of the road traffic moving at least 750 miles was moved by American railroads instead, annual fuel savings would be around 1.2 billion gallons, and annual carbon emissions would fall by approximately 13.1 million tons.