Mystery gas shuts Melbourne airport terminal

CANBERRA - A mystery gas which closed airline Virgin Blue's Melbourne terminal yesterday morning remained unidentified late last night.

Forty seven people were taken to hospital after being affected by the fumes. All were discharged after treatment.

Thousands of passengers were stranded by the emergency.

Exhaust fans were run at full capacity to stop the gas leaking into the Qantas and international terminals, and fire brigade sniffer units were called in to to track the fumes.

Although hazardous materials experts and medical tests have not identified the gas, an airport spokesman ruled out sabotage, saying the leakage was industrial, rather than criminal.

But Metropolitan Fire Brigade spokesman Keith Adamson said an airport terminal did not usually have a wide range of toxic or dangerous chemicals.

"I suppose you've got jet fuel and stuff like that, but we're at a bit of a loss to work out what it could be."

Virgin had to stop all outgoing flights from Melbourne and divert passengers from incoming jets to a nearby freight building.

The drama began about 7.30am local time when one person, believed to be a Virgin staff member, felt ill.

Within two hours the extent of the crisis was apparent, as 20 ambulances ferried 38 people to hospital and another nine made their own way there.

Eight others declined treatment.

All became violently ill without warning. Symptoms included nausea and vomiting, shortness of breath, and dizziness.

Most were reported to be Virgin staff, security officers and other airport workers.

As the airport's emergency response plan swung into action, hundreds of people were evacuated, the terminal was shut and sealed off, and exhaust fans were turned on to full power to prevent contamination of other terminals.

Qantas and international flights continued uninterrupted.

"I smelt something funny and about two minutes later we were evacuated," Paul Kemp, 27, told Melbourne's Age newspaper.

"I thought it was an ammonia-type smell, but I wasn't sure."

Another passenger, identifying herself as Jasmine, said: "We were standing in line and I just felt hot and my stomach was churning. I just wanted to sit down."

Eight fire engines and 35 firefighters arrived about midday to seal off the terminal and try to find and identify the what the Metropolitan Fire Brigade described as noxious fumes.

In the early evening the number of emergency units at the airport had increased.

"We've probably got 15 trucks there," Adamson said.

"We've got our hazardous materials unit out there and we've got gas detectors sniffing around.

"It is confined to the Virgin terminal, so the air handling system is on full exhaust so it doesn't go into any other parts of the airport, so international flights and Qantas flights can still go out. But because it's on full exhaust it's very hard to get any readings."

The terminal reopened shortly after 8pm NZT with the outbreak still a mystery.

"The source has not been located or identified," the brigade spokesman said late last night.

"All [chemical detection] readings are showing zero. Unfortunately, whatever it was has now dissipated."

"We're trying to move as many people as we can tonight," Virgin Blue spokeswoman Amanda Bolger said.

About 20,000 people, including travellers and those dropping off and picking up passengers, were disrupted by the closure, airport spokesman Geoffrey Conaghan said.

- additional reporting AAP