Three people were injured, two of them critically, in a blast at a service station in Westonaria on the West Rand, on Tuesday, paramedics said.
"Reports from the scene indicate that a welding gas cylinder exploded, causing the three men to sustain severe burns," Netcare 911 spokesman Chris Botha said.
Two men were critically injured and another in a serious condition.
Paramedics placed one of the critical patients on a ventilator before airlifting him to Netcare Milpark Hospital.
The other men were taken to a hospital in Krugersdorp.