More than 95 percent of workers who sued after being exposed to the toxic dust that blanketed Lower Manhattan after the World Trade Center fell have joined a legal settlement that will pay more than 10,000 of them hundreds of millions of dollars, officials announced Friday.

The overwhelming acceptance of the deal will mean an end to the bulk of litigation over New York City's failure to provide protective equipment to the army of construction workers, police officers and firefighters who spent months clearing and sifting rubble after Sept. 11.

Thousands sued, claiming that the ash and soot at the site got into their lungs and made them sick. Only 520 of the 10,563 eligible plaintiffs declined to take the offer.

"This settlement is a fair and just resolution of these claims, protecting those who came to the aid of this City when we needed it most," Mayor Michael Bloomberg said in a statement.

Paul Napoli, a senior partner with the law firm representing most of the workers, called the settlement "the best result, given the uncertainty of protracted litigation."

The settlement, which has been on the table since the spring, won approval by the thinnest of margins. Under terms of the deal, it would only become effective if at least 95 percent of eligible plaintiffs signed on. It just cleared that hurdle, with 95.1 percent.

The settlement will provide at least $625 million to the workers, although related deals with other defendants, including the Port Authority of New York and New Jersey, could boost that total to more than $725 million.

Workers could have qualified for an even larger total, topping $800 million, if enough workers had accepted the offer.