Canadian
The Alberta Centre for Injury Control & Research [1]has adopted and endorses the Canadian Paediatric Society Position Statement (IP 2004-01) Preventing injuries from all-terrain vehicles.

Canadian Pediatric Society- Position statements for the Injury Prevention Committee [2]

Pediatric surgeons call for ATV kid ban
[3]Spring 2008 has brought a rash of all-terrain vehicle injuries and deaths across Canada, including the deaths of a two-year-old and a 13-year-old – and a call from the Canadian Association of Pediatric Surgeons to ban children under 16 from driving or being passengers on the increasingly popular vehicles. Laws regulating ATV riding vary widely across the country.
[Source: SmartRisk Navigator]

NLPHA/ARNNL/NLMA Joint Position Statement On ATV Safety [4]

The Nova Scotia legislature has passed strict new rules for all-terrain vehicles. [5](CBC News - Dec 2005)

International
Farm Safe Australia [6]- policy creation

Safe operation of All-terrain Vehicles and All-terrain Utilities on Australian Farms - An Industry Strategy 2004-2009 [7]

New ATV Recommendations from Safe Kids USA [8]- after an extensive review of the data, Safe Kids Worldwide has concluded that there is no way to make ATV riding safe for children and recommends that no children under the age of 16 be allowed to ride an ATV under any circumstance.