UPDATE: A GAYNDAH man has told of the moments he used a garden hose to help his neighbour who was on fire.

Michael Richards said his neighbour was engulfed by flames as he grabbed to hose and went to his aid.

"He was fully alight, all his clothes gone except one sock and jocks," he said.

The man has been flown from Gayndah Hospital to Brisbane in a critical condition.

EARLIER: A DROPPED cigarette has had devastating concequences for a Gayndah man in his 70s after the couch he was sitting on went up in flames.

The man suffered burns to more than 70% of his body before neighbours used a garden hose to put out the blaze.

A Queensland Ambulance Service spokesman said remarkably the man was still conscious when paramedics arrived at the Gayndah address in Pings Lane about 8.30am today.

The QAS spokesman said it appeared the foam couch the man was sitting on had no cover and was highly flammable, causing it to burn extremely quickly.

The man was taken to Gayndah Hospital but is expected to be transported to Brisbane.