A liquid oxygen leak behind Dartmouth General Hospital closed down a portion of Pleasant Street on Tuesday morning.
The area has since reopened to traffic.
"We have to keep the people and pedestrians and vehicles away until we can stop these leaks and also make sure it's safe before we allow people around it," said Halifax Regional Police Const. Pierre Bourdages.
Lloyd Currie, division commander with Halifax Regional Fire, said fire crews were called after staff at the Dartmouth General Hospital noticed a leak at approximately 6 a.m.
"They had a small leak in the bottom of their oxygen tank that supplies the hospital so they gave us a call and we confirmed there's a leak on the front side of the valve so what we did is we attempted to turn the valve off," he said.
"It's pretty iced up, the ice is about a foot thick on the bottom of the tank."
Currie said the hospital has had to go on their back up oxygen supply system. He said a technician is on the way to inspect the tank.
"Right now the amount that's leaking out is not dangerous," said Currie.
He said crews shut down a 150-metre radius — including parts of Pleasant Street, Mount Hope Avenue and Acadia Street — as a precaution.