Jimmy Sullivan prepared for his job as a bricklayer the same way every morning for years: injecting a shot of heroin before leaving his car.

The first time he overdosed on the job, in 2013 at a Virginia construction site, a co-worker who is his cousin stealthily injected a dose of Narcan, an opioid antidote, into Mr. Sullivan’s leg. He woke up and went straight back to work.

The second time, in 2014, his cousin revived him again, and after resting for an hour in his car, Mr. Sullivan was back on the job. His boss told him not to let it happen again. But within a month, Mr. Sullivan had again overdosed on the job site. This time, another worker called 911. After a few hours at the hospital, he went back to work.

As the opioid epidemic continues to rage across the country, with a record 72,000 drug overdose deaths estimated in 2017, the fallout is increasingly manifesting itself at construction sites, factories, warehouses, offices and other workplaces. A stunning 70 percent of employers reported that their businesses had been affected by prescription drug abuse, including absenteeism, positive drug tests, injuries, accidents and overdoses, according to a 2017 survey by the National Safety Council, a research and advocacy organization.

By Jenny Gold