"[My staff] used water containers off the forecourt. Water was poured on him."
Mr Gillies said his staff got to the man quickly, and continued applying cold water even after ambulance staff arrived.
"There was good, fast action from members of public. It was right near a bus stop so the public raised the alarm and called emergency services."
Mr Gillies said there was absolutely nothing to indicate anything untoward when the man purchased the fuel.
He had organised trauma counselling for his staff and said there was "widespread impact" from the incident.
An ambulance took the man to hospital while the Fire Service cleaned the scene of the incident.
Acting Senior Sergeant Tristan Murray of Tauranga Police thanked the five members of the public who helped the man, including an off-duty nurse.
Mr Murray said Police organised Victim Support counsellors for the members of the public who attended the incident.