The highest security will be in place during the APEC leaders' week which includes the long weekend from September 7 to 9. "Our intent around communicating is to be in a position where, as much as possible, there are no surprises for anybody when it comes to Leaders Week," she said.

"[People will know] whether a bus stop has been moved or that their garbage will be collected ... and that businesses know whether their staff will have access to their premises." Ms Ryan said staff at hotels, where important delegates and dignitaries will be staying, must pass an accreditation process and a security background check. Journalists covering the event also have to go through a similar process.

"The NSW Police Force and the [APEC] Task Force are very keen for [open communication] to happen, but at the same time without compromising any information about security that would give any mischief-makers information that they should not have," Ms Ryan said. The Prime Minister's office has said that the Australian Security Intelligence Organisation was conducting security assessments for APEC, including "politically motivated violence checks against ASIO databases, similar to those conducted for the aviation and maritime sectors and a string of special events including ... the 2000 Olympics and the Melbourne Commonwealth Games."

Ms Ryan said anyone with a legitimate reason to be in the city during the summit in September would be allowed to go about their normal business. A business group said they expected Sydney would be as quiet "as a Sunday morning" during the APEC long weekend. "It will be like when you walk around on a Sunday morning and it's hard to find a good coffee," the Sydney Chamber of Commerce's executive director, Patricia Forsythe, said.

"The retail hubs will look the same, that will give you a sense of what it will be like because people don't come in." Ms Forsythe expects most small retailers and businesses in the city to shut during the three-day weekend but many bars and restaurants to open.

"I have no doubt that it will be small business in the city that will find it difficult," she said. The chamber's members, which comprises large corporations, were supportive of APEC and expected to carry some cost from the "inefficiencies" that the summit caused, Ms Forsythe said. She was unable to quantify the cost of the summit to business, noting a generic figure of $327 million as the cost of a public holiday in NSW.

Ms Forsythe said businesses were more concerned about the "unpredictable" nature of any protests than the known disruption of security measures. Ms Ryan said organisers have run about 400 stakeholder briefings about the event for groups such as businesses and residents in the central business district and other APEC security areas.