The Zero AIrailroad 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.

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