Installing an LPG or CNG system in your vehicle
If you want to install an LPG or CNG fuel system in your vehicle, the system must comply with an approved standard:
- LPG systems installed after 1 July 2005 must comply with AS/NZS 1425 LP Gas for fuel systems for vehicle engines.
- CNG systems installed after 1 July 2005 must comply with AS/NZS 2739 Natural Gas (CNG) for fuel systems for vehicle engines.
We recommend that you have the system installed professionally. And, before you can use your vehicle, you need to obtain:
- an alternative fuel installation certificate, and
- an alternative fuel inspection certificate.
Most professional installers are authorised by the NZTA to issue these certificates.
Getting an installation certificate
Once the LPG or CNG system is installed, an authorised vehicle inspector must inspect the vehicle to ensure that the LPG/CNG system complies with the applicable standard. The inspector will check to see that the installed fuel system and its parts meet the required standards. The inspector will then certify the installation and issue you with an installation certificate.
The standards also require an installation compliance plate for each LPG/CNG container. These plates are attached to the inside of the engine bay.
Getting an annual inspection certificate
When you’re issued with the installation certificate, the inspector will also issue you with an inspection certificate – this is valid for one year. As long as the LPG/CNG system remains in working order, regardless of whether you actually use the system, you’ll need to obtain a new inspection certificate every 12 months.
For each annual inspection you need to present your installation certificate. The inspector will carry out detailed safety tests and inspect the system components to ensure they are safe before issuing another inspection certificate.
See more detailed information about inspection requirements (PDF, 2.08MB).
Your vehicle cannot pass a warrant of fitness (WoF) or certificate of fitness (CoF) inspection without a current alternative fuel inspection certificate. The WoF or CoF inspector will also carry out a basic check of the system to ensure there are no obvious leaks or loose components.
See more detailed information about WoF and CoF requirements (PDF, 279KB) for LPG and CNG systems.
