A Fire and Emergency New Zealand (Fenz) appliance was called to a fire in a burn pile near Henley about 3.15pm on Thursday.
A Hato Hone St John spokesman said a helicopter, an ambulance and two rapid response vehicles attended the incident.
One person was airlifted to Christchurch Hospital in serious condition, the spokeswoman said.
Outram Volunteer Fire Brigade Chief Fire Officer Stu Casey said the injured man had been trying to light a fire with fuel and was tended to by St John before the crew from Outram arrived.
The appliance spent only about 15 minutes at the fire as it was under control when they arrived, CFO Casey said.
Fenz community risk manager Otago James Knapp said WorkSafe had been informed of the incident and the scene was under their control.
As the incident might be subject to a WorkSafe investigation he said it was not possible to comment on the incident in detail.
In general, the best practice was to use a gel or solid fuel starter when starting a fire.
"Using flammables there’s always the potential for things to happen unexpectedly," Mr Knapp said.
The initial request for assistance had come from St John and the fire had not been out of control as initial reports had indicated.
The farmer at the property where the fire happened had applied for a permit and Fenz had done a site inspection.
"The permits are not to control people, they’re so that we can engage with people ... Unfortunately in this particular case it’s gone a little bit wrong, but they were trying their best," Mr Knapp said.
From the perspective of managing the burn, there were no concerns about the fire spreading and there had been everything on site that was needed to manage the fire.
In the case of injuries from a fire, the main thing to do was to cool it as fast as possible, Mr Knapp said.
If water was not available, soft drinks or beer would work and the idea was to submerge the wound in liquid for 20 minutes.
In the case of smoke inhalation it was important to have people checked out so they did not develop respiratory issues later on, Mr Knapp said.