HALIFAX -- A Halifax container port was bustling Saturday after being shut down for more than a day when cylinders carrying radioactive material fell about six metres as they were being unloaded from a ship.

Calvin Whidden, senior vice-president for Cerescorp, said work at the Fairview Cove container terminal in the city's north end resumed at 8 a.m. Saturday after experts wrapped up their examination of the area and confirmed there was no leakage of granular uranium hexafluoride.

"(The experts) arrived at the terminal, went onboard the vessel and determined that there was no breach of cargo, no leakage whatsoever and cleared us to go back to work because there was no contamination whatsoever," said Whidden on Saturday.

The city's fire department said emergency crews left the scene around midnight Saturday after the investigation was complete and a 150-metre evacuation zone was lifted.

Whidden said workers would unload two container ships that had been waiting since work stopped on Thursday night, when four steel cylinders encased in concrete, each weighing about 4.5 tonnes, fell from a pallet as they were being lifted off the ship and landed in a contained area of the vessel.

Firefighters evacuated the immediate area as a safety precaution after the accident and the crew of the Atlantic Companion -- which arrived in Halifax from Liverpool, England -- were taken to a local hotel.

Whidden said the cylinders would be taken off the ship Saturday afternoon and would depart on a truck to their destination in Columbia, S.C., next week.

The port was expected to clear the backlog of work by Sunday afternoon, said Whidden.

"We were taking no chances and the safety of our employees and the local people were far more important than the delays of the ships," said Whidden, adding that the port's customers were understanding of the situation.

"Until we were totally, 100 per cent confident that everyone was OK to return, we wouldn't."

URENCO has said the cylinders came from its enrichment facility in the United Kingdom. Uranium hexafluoride is the chemical compound used in the gas centrifuge process to enrich uranium.

URENCO's website says it is an international supplier of enrichment services for nuclear fuel used to generate electricity.

The fire department said there was a similar incident at a Halifax port in the late 1990s involving uranium hexafluoride, but there was no leakage.