New Mandatory National Standard for Automotive Compressed Natural Gas Sets Minimum Methane Number at 65

On August 24, 2024, the State Administration for Market Regulation (Standardization Administration of China) approved and released the mandatory national standard "Compressed Natural Gas for Vehicles" (GB 18047–2026), which will take effect on August 1, 2027. The new standard specifies that the methane number of vehicle-grade compressed natural gas must be no less than 65, aligning with European standards. When the methane number is below 70, refueling stations are required to prominently display the exact value at their business premises. The standard introduces new requirements for methane number and interchangeability, stipulating that compressed natural gas for vehicles within the same region must be mutually interchangeable to ensure that switching between different gas sources does not adversely affect engine performance or safety. Regarding test methods, the standard adds or revises testing procedures for higher heating value, total sulfur, hydrogen sulfide, carbon dioxide, oxygen, water dew point, and water content. It also introduces the Propane Knock Index Method (PKI-MN method) as the referee test method for determining the methane number. Additionally, a new standalone chapter on "Sampling" has been added, specifying that sampling points must be located at the custody transfer point of vehicle-grade compressed natural gas. The standard further clarifies that a product is deemed compliant only if it meets all quality requirements; otherwise, retesting is required.