The flashpoint of candle fragrance oil is the temperature at which point it becomes combustible if exposed to a spark or flame. The flashpoint is generally only important for those making gel candles and for determining shipping methods. Certain gel waxes require fragrance oils with a flashpoint of 170° or higher. The flashpoint of candle fragrance oil can also determine whether or not it can be delivered via air mail or must be shipped via ground.
Despite some fragrance oils having lower flashpoints, they are safe to use in melted wax as long as they do not come in contact with an open flame or spark. Pouring fragrance oil with a flashpoint below 185° into wax that has been heated to around 185° will not cause it to ignite.