I found this on the PGDB website
Check this out and have your say

22 June 2011 - HAVE YOUR SAY

Standards NZ is now inviting public comment on their draft standard on safety verification of existing gas installations (DZ5255).

Click here to view the draft standard. Comments are due to Standards NZ by 12 July 2011.
http://www.standards.co.nz/draft-standards/new-zealand-standards/?action=browseDrafts&draftTypeId=1&mod=drafts

Seems that no one wants to have a long consoltation period just in case someone actualy has any objections

Linkback: https://www.plumbers.nz/regulations-codes-and-standards/73/possible-new-standard-for-gas-audit/701/