A Hunter Valley Police District spokesperson said the boy, who was visiting the property, was thrown from the quad bike after it appears to have slid down a steep section of the track.

The boy sustained suspected spinal injuries, and was treated by ambulance paramedics and taken to Cessnock Hospital before being airlifted to John Hunter Hospital in a stable condition.

The helicopter was also tasked the Cessnock area on Wednesday night, after a 40-year-old man suffered a head injury in a fall at a Millfield property.

The man was flown to John Hunter Hospital in a stable condition.

Meanwhile, Thursday's quad bike accident came just hours after the federal government announced new rules for quad bikes would be rolled out.

Assistant Treasurer Michael Sukkar on Thursday declared that the law would change given an estimated six people a day present to emergency hospital departments and an average of 16 people per year are killed in quad bike accidents.

"Quad bikes are the leading cause of fatalities in Australia of all consumer products that aren't regulated," Mr Sukkar said.

"This safety standard aims to address the high risk of rollovers, which is especially important for many of our farmers and their families who use these vehicles daily."

The Australian Competition and Consumer Commission welcomed the law changes, which require that all new quads within 12 months have information affixed to them about the degree of slope they can handle before rolling.

Within two years, they will have to conform to minimum standards for stability on sloping surfaces.

"These changes are an important step in improving the safety of quad bikes, and we look forward to working with farmers, manufacturers and retailers, to implement the standard," ACCC deputy chair Mick Keogh said.

- with The Newcastle Herald