A man is being treated for facial burns after the back of his ute caught fire while he was filling a jerry can at a south Canberra service station.

Firefighters were called to the Caltex petrol station in Conder about 9:00am on Monday, but staff at the petrol station were able to extinguish the fire before emergency services arrived.

The man, in his mid-30s, suffered facial burns in the flare-up and was tended to by paramedics on the scene before being taken to Canberra Hospital.

The fire was sparked by a refrigerator running on the back of the man's ute, next to where he was refilling the jerry can.

"Petrol is extremely volatile liquid, and it will flash quite easily, and it is really important when you're filling a jerry can to take it out of your vehicle … and place it on the ground where it's earthed properly," Leigh Curtis from the ACT Emergency Services Agency said.

"Static electricity can be a problem which can also cause an ignition.

"It's a requirement that is shown on all of the signage at petrol stations, and it should be common practice."

Mr Curtis said the refrigerator should also have been turned off before the man began filling the can.

The petrol station was closed for several hours on Monday morning. Firefighters have declared the area safe.