What are the differences between National Standard gasoline and Beijing Standard gasoline?

[OCamilla]

Here are the differences between National Standard gasoline and Beijing Standard gasoline: 1. Different standards: Beijing Standard is a local standard, while National Standard is a national standard. In terms of standard hierarchy, the National Standard is generally set more broadly to accommodate differences across various regions in the country, whereas local standards are more tailored and stricter to suit the actual conditions of the region. Due to Beijing's high environmental protection requirements, the Beijing Standard gasoline is also the highest in the country. 2. Different gasoline prices: National Standard gasoline is more expensive than Beijing Standard gasoline. Below is some related information about gasoline grades: 1. Grade specifications: Gasoline is produced and sold according to grades, which are specified by national gasoline product standards and are related to different standards. Currently, China's National (IV) gasoline has three grades: 90, 93, and 97. National (V) gasoline grades are 89, 92, and 95 (with 98 available in the appendix). Gasoline grades are classified by octane rating. 2. Anti-knock performance: 97-grade gasoline refers to gasoline fuel with anti-knock performance equivalent to a mixture of 97% isooctane and 3% n-heptane. The higher the grade, the better the anti-knock performance. Different grades of gasoline should be selected based on the engine's compression ratio, which is indicated in each vehicle's user manual. Mid-range cars with a compression ratio between 8.5 and 9.5 should generally use 90-grade (National IV) gasoline, while cars with a compression ratio greater than 9.5 should use 93-grade (National IV) gasoline.