Orange Shirt Guy

Why do some escalator rails run at a different speed from the steps alongside them?

the handrails.  Because the steps and the rails run in a continuous loop, the descending halves of the stairs and handrails act as a counterweight to their respective ascending halves.  The handrails, then are totally friction-driven rather than motor-driven.

     If the escalator is properly maintained, the handrail should move at the same speed as the steps.  The handrails are meant to provide a stabilizing force for the passenger and are thus designed to move synchronously for safety reasons.  Handrails that move slower than the accompanying steps are actually dangerous, for they give a passenger the impression that his feet are being swept in front of him.  Richard Heistchel, of Schinder Elevator Company, informed Imponderables that handrails were once set to move slightly faster than the steps, because it was believed that passengers forced to lean forward were less likely to fall down.

Feldman, D. (1989). When Do Fish Sleep and Other Imponderables of Everyday Life.  New York: Harper.