PROVIDENCE — Foreseeing a large turnout of protesters, the city has marked certain designated areas for demonstrations and is asking protest groups to register prior to the start of the annual gathering of the U.S. Conference of Mayors, which opens here Friday.

A registration form and information about the protest areas were posted on the city’s Web site early Tuesday. At least eight groups expected to protest have been contacted by Mayor David Cicilline’s administration:

•Local 799, International Association of Fire Fighters

•Lodge 3, Fraternal Order of Police

•AFL-CIO

•Local 217, United Here

•RIFuture.org

•People for the Ethical Treatment of Animals

•Direct Action for Rights and Equality

•Local 1199, Service Employees International Union (Providence Head Start employees)

Peter Gaynor, director of the city’s Emergency Management Agency, said he is determined to respect protesters’ First Amendment rights while ensuring the safety of those who live, work and visit the city.

“Any protest will not affect the resources necessary to support public safety,” Gaynor said. There will not be any penalty for protesters that fail to register, he added.

Paul Doughty, president of the firefighters local, said his union was not made aware of the designated areas for protesters and that it might pursue legal action.

“We’re not comfortable with this. They’re changing the rules. In the past, we’ve agreed to allow attendees to enter an event without having to pass through a picket line, but that’s when they have asked,” he said. “This is another attempt by the administration to minimize our efforts.”

The firefighters and police unions say they plan picketing on all four days of the conference. Both unions are both locked in a contract stalemate with the mayor.

Union leaders said members would demonstrate during the convention hours — from 9 a.m. to 5 p.m. — and in the evening hours at a number of social events to be held at several locations.

The police union president, Lt. Kenneth Cohen, called it an “informational” picket. “We’re not striking. We’re not demanding anything. It’s about the mayor negotiating in good faith,” he said. “It’s about bringing to light the fact that what the mayor says is not really reality.”

Gaynor said that the city has designated the area across the street from the Rhode Island Convention Center (the Providence Journal side of Sabin Street), from Dorrance to Matthewson streets, as the “public viewing” area for groups intending to protest activities at both Convention Center and the Westin Providence Hotel, where a large number of conference participants are staying.

Areas directly around the convention center entries will be closed to the public. On Tuesday, barricades were already being positioned on Sabin Street. “The general rule of thumb is that protesters should be within sight and sound of the event,” said Gaynor.

There will be designated areas at conference social events, such as a dinner at the Bank of American Skating Rink scheduled for Friday night and a picnic at Roger Williams Park on Monday evening.

The firefighters and police unions say they expect a large turnout for the protests. Union officials say they are drumming up support from unions across the state and country for its picket line.

“We have the support of the State Association of Fire Fighters, so you’ll see someone from every one of the fire departments in the state,” said Doughty, of the firefighters union.

The unions are planning for the highest numbers to come out on Saturday and on Monday, near the start and at the end of the conference.

Gaynor, of the EMA, said the city expects additional protesters, including Local 217 of United Here, which was planning an informational picket. The union represents workers at the Convention Center and downtown hotels and it is unclear what impact a possible picket would have on the mayors’ conference. Calls and e-mails to union officials were not returned on Tuesday.

There is no clear count of how many will be ultimately be out there at any given time and no protest groups had registered as of late Tuesday. “We think other mayors will bring their own protesters,” said Gaynor. “We’ll probably get a few more groups that we didn’t expect and that we have not accounted for.”

Police Chief Dean Esserman says the city will not enlist other local police departments, the state police or the National Guard to assist in policing the event. “We’ve done protests before. We’ve done political protests before. And we’ve done fire department and police department protests before,” he said.

Esserman would not say how many of the Police Department’s nearly 500 officers he would deploy or speculate on how much the city might incur in overtime costs for securing the conference.

He said that officers who are off duty will be allowed to participate in the protest, but that those assigned to work those days must report to duty.

“We’re optimistic that that will not be a problem that we’ll encounter,” he said of the possibly of being short-staffed during the conference. “Public safety comes first, and our men have honored that in the past.”

pmarcelo@projo.com