All modifications to a vehicle must have specific approval from VicRoads or be carried out in accordance with guidelines published by VicRoads. This is a requirement of Regulation 293 of the Road Safety (Vehicles) Regulations 2021.
Conversion of an existing motor vehicle to operate on Liquified Petroleum Gas (LPG), Liquefied Natural Gas (LNG) or Compressed Natural Gas (CNG) is a modification.
Guidelines for gas conversions
VicRoads’ Vehicle Standards Information 27 VSI [PDF 509 Kb] sets out the requirements for an LPG, LNG or CNG conversion.
Any LPG, LNG or CNG conversion carried out in accordance with VSI 27 is an approved modification.
VSI 27 also includes the Conversion Report that vehicle owners must present to VicRoads to notify them of a change in fuel type.