Gregory Echevarria, 34, was crushed by a crane's counterweight in lower Manhattan; Nelson Salinas, 51, was killed by falling debris while repairing the facade of a Manhattan apartment building; and Erik Mendoza, 23, fell to his death from the roof of a 13-story building in Brooklyn.

The deaths of the three men within days of each other in April spurred New York City's Department of Buildings to pull inspectors from across the agency to conduct a two-week-long sweep of construction sites across the five boroughs. By the time they were finished, they had visited 6,493 work sites, ordered 322 to halt construction immediately, and issued 1,081 additional safety violations.

"Every worker should be thinking about safety first," said Acting Buildings Commissioner Thomas Fariello. "It's not just a saying, it's real."

Fariello said the agency pulled dozens of inspectors off of their normal rounds for the crackdown. Over the course of the spot inspections, they found a lack of fall protection at some workplaces and at others, they realized that site superintendents were failing to make sure safety precautions were up to snuff. There were also cases of out-of-date safety plans posted at job sites—if they were posted at all.

"We want every worker that comes to work to be able to go home in the same shape that they came in and go back to their families," said Fariello.

In order for the shuttered sites to be able to resume construction, they must fix the issues and have a Buildings Department inspector make a second sweep to check their work. And starting in June, the department will start fining contractors and developers who fail to report deaths or injuries that occur on building sites.