CN code 8702 30 covers buses equipped with spark-ignition engines (petrol or gas – CNG, LNG, LPG), designed for transporting ten or more persons including the driver. In practice, this segment is dominated by buses powered by compressed natural gas (CNG), which represent a popular alternative to diesel buses in urban transport, offering lower particulate matter and nitrogen oxide emissions. CNG buses are fitted with methane-fuelled spark-ignition engines, with pressure vessels mounted on the roof or under the floor. These engines must meet Euro VI emission standards, and pressure vessels are subject to UNECE Regulation No 110 on CNG and LNG-powered vehicles. Bus type-approval is carried out under Regulation (EU) 2018/858, and body construction must comply with Regulation No 107. In 2026, CNG buses are treated as a transitional solution – offering lower CO2 emissions than diesel but not meeting the zero-emission criterion.

When importing buses with spark-ignition engines (CN 8702 30) from third countries, standard customs procedures apply. The importer presents a commercial invoice, transport document, customs value declaration, and certificate of origin. Duty rates depend on the country of origin and should be checked in TARIC/ISZTAR4. Buses are not subject to excise duty. VAT is charged on the customs value plus duty. The vehicle must hold EU type-approval, including approval for CNG/LNG pressure vessels under UNECE Regulation No 110. Transporting buses with CNG pressure vessels requires consideration of ADR regulations for vehicles with gas installations. Gas bus registration in Poland requires a technical inspection addressing specific requirements for vehicles with gas installations, including system tightness and vessel condition. Gas buses imported for public transport may be subject to additional requirements arising from service agreements with the transport organiser.

Buses powered by compressed natural gas (CNG) form a significant segment of the spark-ignition engine bus market (CN 8702 30) in Europe. Major manufacturers – Solaris (Urbino CNG), Iveco (Crossway LE CNG), MAN (Lion's City CNG), Mercedes-Benz (Citaro NGT), and Scania – offer models meeting the highest emission and safety standards. Advantages of CNG propulsion include lower particulate and NOx emissions compared to diesel, lower noise levels, and the potential to use biomethane as a renewable fuel. Limitations include shorter range compared to diesel (typically 350-500 km), the need for CNG refuelling infrastructure development, and higher pressure vessel costs. The AFIR regulation obliges Member States to provide CNG and LNG station networks along the TEN-T network. Market outlook for CNG buses depends on the pace of urban transport electrification – in countries with developed CNG infrastructure, gas buses may remain competitive for the coming years.