Over the past decade, states have slashed workers’ compensation benefits, denying injured workers help when they need it most and shifting the costs of workplace accidents to taxpayers.

Dennis Whedbee’s crew was rushing to prepare an oil well for pumping on the Sweet Grass Woman lease site, a speck of dusty plains rich with crude in Mandaree, North Dakota.

It was getting late that September afternoon in 2012. Whedbee, a 50-year-old derrickhand, was helping another worker remove a pipe fitting on top of the well when it suddenly blew.

Oil and sludge pressurized at more than 700 pounds per square inch tore into Whedbee’s body, ripping his left arm off just below the elbow. Coworkers jerry-rigged a tourniquet from a sweatshirt and a ratchet strap to stanch his bleeding and got his wife on the phone.

“Babe,’’ he said, “tell everyone I love them.”

It was exactly the sort of accident that workers’ compensation was designed for. Until recently, America’s workers could rely on a compact struck at the dawn of the Industrial Age: They would give up their right to sue. In exchange, if they were injured on the job, their employers would pay their medical bills and enough of their wages to help them get by while they recovered.