Children should never be allowed to ride quad bikes, says an agricultural safety expert.
"There is no way in the world would I allow a child onto one," says Associate Professor Tony Lower of the Australian Centre for Agricultural Health and Safety.
Prof Lower is co-author of a study in the Medical Journal of Australia that shows quad bikes are dangerous and suggests that they be replaced with other vehicles where possible.
The study by Monash University and the University of Sydney shows there were 19 quad-bike deaths and 800 hospital admissions in Victoria over the nine years to the end of June 2011.
The problem would be similar in other parts of Australia, says Prof Lower and his organisation reports 12 deaths across Australia in the first eight months of 2013.
Most of the deaths reported in the medical journal involve farm use, but an increasing number of vehicles are being used for recreational purposes.
Most injuries involve experienced adult riders, but more than 15 per cent involve children.
One of the biggest dangers is the quad bikes are fundamentally unstable and prone to rollover. They can flip and crush their rider.
This happens even with the ones marketed for use by children, says Prof Lower.
He points out that Surf Lifesaving Australia is replacing its quad bikes with safer vehicles that do the same job.
And the journal article recommends that farmers do the same.
If quad bikes must be used, then crush-protection devices should be fitted, it says.
"Children must not ride quad bikes and passengers must not be carried."
Prof Lower says he would prefer if farmers let their children ride two-wheel motorcycles, with appropriate protective gear including a helmet, instead of quad bikes.
"When they do come off they may injure themselves but the chances of them dying are significantly less than on a quad bike.
"People visiting farms should not use them unless they are skilled. We do see deaths in visitors to farms."