If irritating large commercial real estate companies is part of the goal of the Occupy D.C. protests, it appears to be working.

D.C. police officers tape off the entrance to the National Air and Space Museum as Occupy D.C. demonstrators approach. (Jose Luis Magana/AP)

Richard Bradley, executive director of the Downtown Business Improvement District, which represents commercial property owners, said some of his members with properties near the two protest areas called him to ask what was being done to address the demonstrations as they persist.

“We really want to know what the definition of ‘temporary’ is,” Bradley said. “Some people said they will be there for four months. Are there propane in those tents? There are health issues, there are safety issues associated with that.”

Bradley said he wanted to make sure that protestors were granted their First Amendment rights but wondered how long occupying public places would be part of that. “Is there ever a line that gets drawn? How does sleeping in a park contribute to that expression?” he said.

Bradley contacted officials at the National Park Service “expressing concern and urging them to closely monitor activities in the parks,” according to an e-mail Bradley’s staff sent to business district members this morning. Recipients include some of the city’s biggest landlords, such as Hines Interests, Tishman Speyer, Douglas Development and the General Services Administration.

“While the Downtown BID recognizes First Amendment rights, we question NPS allowing overnight stays, structures to be erected in the parks and cooking using flammable materials,” the e-mail read. “In addition, the Downtown BID is requesting that Park Police be assigned to secure the parks 24/7, parks maintenance crews be deployed regularly and parks funding be secured to repair damage to the parks.”

Bradley said the e-mail was aimed at improving coordination between the Park Service, city officials and the business district, which employs clean-up and safety staff downtown.

Terry Lynch, director of the Downtown Cluster of Congregations, a group that provides services to the homeless, said there had been problems with trash in the parks in the past and that he hoped the protestors treated the area with respect. He said he was not aware of any injuries or health problems related to the protestors but that health and safety were a concern.

“I’m just hopeful that those who are in the parks are keeping them both clean and safe both for them and other users of the park,” he said.

Staff writer Nikita Stewart contributed to this report.