If you see smoke billowing out of the Lampost on Sunday, do not be alarmed.

The Oak Bluffs bar and nightclub will be the site of a major fire drill Sunday morning from 8 a.m. to noon involving three Island fire departments.

As many as 60 fire and rescue personnel will respond to the scene, where a simulated fire will overtake the second floor dance area, trapping people on the second and third floors with no means of egress.

The drill is the first phase in a process of preparing for a fire in the downtown area, a section of town particularly vulnerable to fast-spreading fires.

“It lays everything out ahead of time so that in the event that we have a real fire on that street, the trucks know ahead of time what their responsibilities are and where they should be going,” said Oak Bluffs fire chief John Rose, who will oversee the drill.

Downtown Oak Bluffs is particularly vulnerable to major fire events. Its old, wooden buildings are positioned close together with little or no separation between them. In mid summer, streets are full of people and vehicles, further complicating the staging of vehicles and other apparatus.

The Edgartown and Tisbury fire departments will participate in the drill, lending a ladder truck and an engine truck each.

The drill will also involve the regional communications center, Oak Bluffs police and emergency medical services, as in the case of a real event. Calls for help will be heard over the scanner.

The Lampost is one of the largest buildings on Circuit avenue. If you include the basement Dive Bar, it has five floors in total, Mr. Rose said. “It’s a perfect opportunity to test our resources,” he said. During the drill, firefighters will practice responding to a Mayday distress signal with new equipment that allows them to quickly locate a trapped colleague.

“The idea is to make it as realistic as possible and to tax our resources to the max,” Mr. Rose said.

The drill will involve 11 to 15 vehicles, which will park on Circuit avenue, and on Lake and Kennebec avenues. Lake avenue will be closed in front of Giordano’s Restaurant and Kennebec will be blocked off from Healey Way to Lake avenue.

Circuit avenue will be open to traffic during the drill, but in the event of an actual fire, it would likely be closed, Mr. Rose said.

“We are trying to be proactive, so that if, God forbid, it happens on Circuit avenue, we will be as prepared as we possibly can be,” the chief said.