| UN R49 Diesel and CNG/LNG Engine Emissions | UN Regulation | UNR 0049 |
| UN R83 Motor Vehicle Emissions | UN Regulation | UNR 0083 |
| UN R85 Power Measurement of Internal Combustion Engines and Electric Motors | UN Regulation | UNR 0085 |
| UN R110 Compressed and Liquefied Natural Gas System Components | UN Regulation | UNR 0110 |
| UN R115 Liquefied Petroleum and Compressed Natural Gas Retrofit Systems | UN Regulation | UNR 0115 |
| GTR No. 15 Worldwide Harmonized Light Vehicle Emissions Test Procedure | GTR 0015 | |
| UN R143 Heavy-Duty Dual Fuel Retrofit Systems | UN Regulation | UNR 0143 |