Specific LPG and CNG retrofit systems to be installed in motor vehicles for the use of LPG or CNG
PNS/UN ECE 115:2006 Uniform provisions concerning the approval of: (a) Specific LPG (Liquified Petroleum Gases) and (b) CNG (Compressed Natural Gas) retrofit systems to be installed in motor vehicles for the use of LPG or CNG, respectively, in their propulsion system