A spate of social media videos showing dangerous barbecue behaviour has prompted warnings from fire safety experts.

One recent video from early this month showed a Launceston man using a gas bottle as a flamethrower, blasting an outdoor barbecue set.

Another video showed a Sydney man suffering serious burns after throwing a bucket of fire-starters onto open flames.

One Launceston man filmed himself using a gas bottle as a flamethrower. (A Current Affair)

Fire and Safety Australia training supervisor John Farrer, who has worked as a firefighter for decades, said the consequences of this kind of behaviour could be "catastrophic".

"Over the years I've seen too many incidents that could be avoided and that's purely with common sense," he said.

"They just need to take a step back, think about what they're doing, and take their time."

A Sydney man tipped a bucket of firestarters onto his barbecue. (A Current Affair)

He had to flee the resulting blaze. (A Current Affair)

Director of the Victorian Adult Burns Service at The Alfred, Dr Heather Cleland, warned against using accelerants to light barbecues or fires.

"When that happens, people can become enveloped in flames and their clothes can catch fire, and they can suffer very significant life-changing or life-ending injury," she said.

She said the majority of patients at the burns unit were "young, fit, healthy men".

Experts have urged people to put safety first around fire. (A Current Affair)

Mr Farrer urged people to check the gas bottle before using the barbecue.

"The simple process would be doing a leak test with soapy water around the connections," he said.