Australian marine pilots Monday called for a review of how ships pass by the Great Barrier Reef, warning of the risk of a major environmental disaster on the tourist attraction.

Australian Reef Pilots, a firm with a century of experience in the region, raised its concerns after a Hong Kong-flagged bulk carrier broke down near the reef on Friday and drifted disabled for more than a day before it was secured.

The company wants to see shipping routes restricted and the area where vessels must use pilots extended, moves which could prompt strong objections from foreign vessels accustomed to free passage.

"This is a second incident in about the last month where we've had a ship drifting outside the Great Barrier Reef but drifting towards it," Australian Reef Pilots chief executive Simon Meyjes told AFP.

"The biggest problem there is that they are in very deep water, they can't drop anchor to stop themselves drifting so they either have to fix their own problem or wait for help to come."

Meyjes said in the latest incident, involving the 186-metre (610-foot), 45,000 tonne bulk carrier ID Integrity, it took close to 48 hours for tugs to reach and secure the vessel as it drifted in the Coral Sea.

The ship broke down north of the Queensland city of Cairns on Friday en route from Shanghai, and floated completely disabled near the world's biggest coral reef, narrowly missing grounding on the outlying Shark Reef.

The Australian Maritime Safety Authority emergency tow vessel Pacific Responder reached the bulk carrier late Sunday to connect a line and was pulling it towards Townsville on Monday.

But Meyjes said the potential disaster could have been dealt with more quickly if all ships were forced to travel in the shipping lanes inside the reef, rather than on the outer edge of the coral and towards open sea.

"Inside the Great Barrier Reef, they are in shallower and protected waters. They can anchor. And obviously they are much closer to help and the response time is much less," he said.

"The risk profile when you're outside the reef and something goes wrong, it's terrible. An oil spill would spread very, very rapidly and you've got a couple of thousands of miles of exposed reef edge."

Meyjes also urged that ships have a local pilot on board when they are inside the Great Barrier Reef area.

Conservationists have long raised fears about the impact of increased traffic on the Great Barrier Reef as Queensland state's coal and gas boom strengthens.

Meyjes added: "There are shipping accidents around the world on a regular basis. I'm not saying that it's inevitable but I am saying that there is certainly risk there that we need to consider."