More than 300 adventure tourism operators slow to engage in a major overhaul of the industry have been issued with reminder letters giving them the hurry up.
Tough new safety standards are being implemented over a three year period, up until November 2014, after which it will be an offence for an adventure activity operator not to be registered and have passed a safety audit.
The Ministry of Business, Innovation and Employment, which is overseeing the project, revealed just 52 out of an estimated 600 operators had signed up to a voluntary public register.
British man Chris Coker, whose son Bradley was one of nine people killed when a skydiving plane crashed at Fox Glacier in 2010, launched a high-profile internet campaign following the accident.