Curious onlookers at a train wreck on the Union Pacific Railroad tracks near Laramie, Wyoming, ca. 1890.

The efforts of the Master Car Builders Association to standardize brakes, couplers, and car design, and the Safety Appliance Act of 1893, brought U.S. railroads into modern times. The Act mandated that all rail lines conducting interstate commerce must use cars that coupled and uncoupled without manual assistance of a worker standing between cars. The Act also required that the trains employ power braking systems that could control the speed of the train without a brakeman to do so manually. The effect of the changes was marked by the dramatic reduction of injury and death to brakemen and passengers.