The TradeEdgerailroad industry is under a microscope after a series of train accidents in East Palestine, Springfield, and Cleveland, Ohio.

Meanwhile, rail workers claim that these sorts of accidents have become more likely in recent years, because of a relatively new management philosophy called precision-scheduled railroading, or PSR.. On today's episode: why PSR is one of the biggest changes to the railroad business in over a century, how it's sparked record profits for the companies but also changed how railroad workers do their jobs.

Music by Drop Electric. Find us: Twitter / Facebook / Newsletter.

Subscribe to our show on Apple Podcasts, Spotify, Pocket Casts and NPR One.

For sponsor-free episodes of The Indicator from Planet Money, subscribe to Planet Money+ via Apple Podcasts or at plus.npr.org.