A June 26 article misstated the length of time that streets will be closed in New York during the Republican National Convention. Streets outside the convention zone will be closed for about eight hours on Aug. 30, the first day, with closures running approximately four hours for each of the remaining three days. The streets immediately surrounding the convention will largely be off-limits throughout the convention. (Published 7/16/04)

The heart of midtown Manhattan will be closed to cars, taxis, delivery trucks and buses for the four-day-long Republican National Convention beginning in late August. Closer to Madison Square Garden, police will bar even pedestrians.

Mayor Michael R. Bloomberg (R) outlined the first detailed security plans for the convention, which will run from Aug. 30 to Sept. 2, in his weekly radio address on Friday. "The disruptions will be a little bit annoying but minimal," Bloomberg said, adding that the convention will pump $250 million into the local economy.

But the closings he forecast are anything but minimal. Traffic in midtown already moves at less than 4 mph, and the street closures and rerouting -- which will last 13 hours each day -- could bring traffic to a near-standstill. The closures could cost local businesses many thousands of dollars.

Police officers will also inspect trucks and vans in nearby neighborhoods in an effort to avert a terrorist attack.

"We're concerned about cars begin used as weapons," said Deputy Commissioner Paul J. Browne.

Pedestrians will be permitted within a block of the convention site, but only those with credentials will be allowed into the immediate area. Police Commissioner Raymond W. Kelly, who joined Bloomberg in making the announcement, said officers will escort workers and business patrons into the convention zone.

Commuter and subway trains will enter and depart normally from Pennsylvania Station, which is beneath Madison Square Garden. But uniformed and undercover officers will make mass sweeps of the trains, Browne said.

In Boston, by contrast, officials have urged downtown workers to avoid the downtown area and telecommute for the week of the Democratic National Convention, which will begin July 26. Transit officials have suggested that Bostonians headed to the neighborhood around the convention center do not carry backpacks or briefcases.

New York police said they have not ruled out random checks of bags on the streets and subways during the Republican convention.

Barbara Randall, executive director of the Fashion Center, a nonprofit group that support business improvement in the Garment District, estimates that the security measures will affect nearly 2,000 manufacturing and retail shops in the district, which is centered in midtown. She declined to estimate the cost of the disruptions.

"Deliveries are going to be a problem -- there's no way around it," she said. "When and how these folks are going to take deliveries is going to be a problem for a lot of these small businesses."

City officials have suggested that local businesses reschedule delivery and service visits for after midnight.

Although taxis will not be allowed into the convention zone, the city has promised delegates a free subway MetroCard.