GB/T 5169.23-2024 is Part 23 of the series of standards for fire hazard testing of electrical and electronic products. It specifies the 500W vertical flame test method for polymer tubular materials, applicable for evaluating the burning characteristics of such materials and providing a basis for quality control and material selection. The standard determines indicators such as afterflame time, flame spread length, and ignitability of drips by applying a specified flame vertically to a supported tubular specimen. The test requires a 500W tubular burner, armored thermocouples, high-precision timing equipment, a specimen vertical clamping device, and a test chamber with a volume of not less than 2 m³ to precisely control flame parameters and environmental conditions, ensuring reliable test results.