"It is a legal duty for all persons conducting a business to ensure so far as is reasonably practicable that the health and safety of other persons is not put at risk from work carried out as part of the conduct of the business.
"This means identifying risks and eliminating them, or where elimination is not possible, managing the risk."
WorkSafe data shows 60 people died on quad bikes between January 1, 2006 and November 31, 2017 in New Zealand.
Another 547 serious injuries were reported.
Rural Women New Zealand (RWNZ) national president Fiona Gower says she was saddened to hear of the death.
"It is very sad, but it need not have occurred," she said.
"We need to prevent families and friends from the heartbreak of losing a loved one in such tragic circumstances.
"RWNZ is concerned on two levels. One is children riding age-appropriate quad bikes unsupervised and the other is children under the age of 16 riding adult-sized quad bikes.
She said the incident is a reminder of manufacturers' recommendations that children under 16 should not be riding adult-sized quad bikes.
"Children do not have the weight, strength or judgement to be operating these vehicles," she said.
"When young children are riding age-appropriate quad bikes, they need to be wearing a helmet and be supervised at all times.
"RWNZ encourage that anyone planning to use any form of machinery on farms receive training and learn safe practices.
"It is heartbreaking to receive news like this."
Gower extended condolences to the boy's family and friends.
A service for Demitrus was held at the Kai a te Mata Marae in Morrinsville on Sunday.
His death has been referred to the coroner.