The flash point of transformer oil typically ranges between 140°C to 160°C (284°F to 320°F), depending on its specific formulation and grade. This property is critical as it indicates the oil’s flammability and safety profile during operation. High flash points are essential for ensuring that transformer oil can safely operate at elevated temperatures without posing a fire risk. Proper maintenance and monitoring of the flash point are vital for preserving the integrity and performance of electrical insulation systems.