GB/T 12575-1990 requires the determination of vanadium content in liquid fuel oil by flameless atomic absorption spectroscopy (AAS). The standard is based on the absorption characteristics of vanadium for specific wavelengths of light. Specify the performance parameters of required instruments, such as Flame Atomic Absorption Spectrometer (FAAS). Detail the method of sample collection and storage to ensure sample representation and Stability. Standardize the test process, covering instrument preheating, calibrating, Sample Handling and determination wavelength selection. According to this standard, the vanadium content in liquid fuel oil can be accurately determined, providing key data support for fuel oil mass assessment, combustion performance research and related industrial applications.