An explosion at a Hawke's Bay school was caused by a parent using a portable gas cooker incorrectly to cook homemade meat patties.
The explosion at Mayfair School on Tuesday burnt the arm of a parent. She was taken to Hawke's Bay Hospital with moderates injuries and discharged later that day.
The portable cooker was used as part of an outdoor education exercise in which students created their own meat patties for parents to cook.
Mayfair School principal Tanya Bunny acknowledged there had been an element of human error but said there was a "strong possibility" of product fault due to the risks posed by misuse of the equipment.
"The exercise for the children was that they designed and created their meat patties, and then the parent helpers cooked them as part of an outdoor education week," she said.