Mineral oil
Overheating the oil bath can result in a fire hazard, especially if mineral oil is being used. Generally, the maximum safe operating temperature of a mineral oil bath is approximately 160 °C, the oil's flash point. Mineral oil can't be used above 310 °C in any cases, due to the compound's boiling point. If higher temperatures are needed, a silicone oil or a sand bath may be used instead.