Three people have died in quad-bike accidents in Northland in the past month, at Kaikohe, Dargaville and Hikurangi.
The Labour Department says quad bikes cannot go everywhere and do everything. They are not all-terrain vehicles.
Northland manager Rod Gibbon says the bikes are very unforgiving when their perfomance limits are exceeded.
Mr Gibbon says that before anyone on a farm rides a quad bike, they should think about whether it is the right vehicle for the job, because it will not be for many tasks.
The department says it is too soon to say exactly what caused the recent fatalities.
On average, five people per year die in quad bike accidents and 850 people are injured.
