A short history of gasfitting in caravans
Once completed all gasfitting work must be certified by a certifying gasfitter.
How is this documented, Minnie?
I don't have any certificate covering my (old) installation - and I doubt that many of us do.
Is it only required for installations completed, or altered, since a particular date?
Gas installation work has always (since 1993) been required to comply with the then current gas installation code.
For a very long time the work didn't have to be carried out by a licensed person if the supply cylinder was less then 15 kg.
In April 2010 all gasfitting became licensed work — the <15kg exemption was removed.
In May 2010 the current gas regulations came into force. The regulations required certification of gasfitting but continued the <15kg exemption from certification.
In July 2013 a new certification regime was introduced that removed the <15kg exemption. All gasfitting from that point must be certified.
Depending on when your gas installation was built the above should tell you whether it should have had certification in the first place.
If you are looking to get something now for your existing gas installation you can ask a gasfitter to do a "Certificate of Verification" under NZS 5255: Safety verification of existing installations
. This certificate won't tell you that the installation is fully compliant with the current requirements (the gasfitter won't be able to do this—he can't see the piping in the walls for instance).
Instead it will be a certificate stating that the installation is not unsafe and may be used.