Two years after plummeting 30 feet from a faulty scaffolding, a Mexican day laborer made history in March with a $4 million settlement, the largest ever granted to an illegal immigrant. While his windfall was unique, however, his working conditions were not. The expansion of New York’s underground construction industry – increasingly dependent on illegal immigrant labor – is contributing to widespread federal safety violations, a study released yesterday concluded.

The analysis of U.S. Occupational Safety and Health Administration statistics by the New York State Trial Lawyers Association found violations in nearly three-fourths of work sites where workers make extensive use of scaffolds and ladders.

“A construction industry where 80% of inspections in certain key trades find violations, and where over a third of the violations receive the most severe gravity score, is not a safe industry,” the study concluded. With concrete work, for example, 86% of sites had at least one violation. A notice from OSHA apparently did not serve as a deterrent in half the cases, as 46% had at least three violations and 34% had at least five violations. In other fields with elevated workers, such as carpentry, masonry, roofing, and painting, similar rates of noncompliance were recorded.

The most frequently violated standards involve scaffolding and fall protection, both of which protect workers at elevated heights.

A labor attorney, Deborah Axt, said that in her experience, employers found the penalty much less expensive than compliance. Ms. Axt, legal director of the Brooklyn immigrant advocacy group Make the Road by Walking, said that in dozens of one-on-one workplace consultations, she had “never had a worker who had OSHA inspect their site.”

The president of the lawyers association, Shoshana Bookson, said the report reinforced the need for a state labor law, referred to as the Scaffold Law. Two bills pending in the state Legislature would repeal the Scaffold Law, on the theory that it addresses an area that OSHA already regulates.

“The federal agency, OSHA, is not monitoring violations adequately,” Ms. Bookson said. “The Scaffold Law is urgently needed – we just can’t depend on OSHA.”

A spokesman for OSHA, John Chavez, said, however, that the report proved the agency was doing its job of inspecting and regulating workplace safety. “They wouldn’t see all these violations if OSHA compliance officers were not out there doing their job, inspecting,” he said.

The report blamed the pervasive violations on the vulnerability of the construction workforce, which is increasingly dominated by illegal immigrants. Since OSHA began collecting information on foreign-born workers’ accidents in New York City in 2001, the study reported, 67% befell immigrant workers. According to statistics from the Department of City Planning, fully 58% of construction workers are foreign-born. With thousands of them illegal and working off the books, the actual percentage is thought to be much higher.