Flash points can be confusing, even for experienced candle makers. Simply put, a fragrance oil's flashpoint is the temperature at which its vapor can ignite when exposed to an ignition source, such as an open flame. This might sound alarming, but it's not as dire as it seems.
Essentially, it indicates the temperature at which the oil may combust when in contact with an open flame or spark. Most fragrance oils we offer have flashpoints ranging from 141°F to 200°F or higher.
You might wonder why fragrance oils with flashpoints lower than a candle’s flame temperature (around 1800°F ) don't burst into flames when used in candles. The answer lies in the need for a large volume of fragrance oil in an enclosed vessel for combustion to occur at the flashpoint. A typical candle with a fragrance load of 6-12% in wax doesn't meet these conditions, so the risk of ignition during candle making is low.
However, fragrance oils are flammable, and there's a hypothetical risk of igniting them at home under certain conditions. But following normal and safe candle making steps would not create such a risk. If too much fragrance oil is used, separation may occur and small drops may appear on the candle's surface, causing a potential fire risk. The best way to avoid this is to check the maximum fragrance oil retention for the type of wax that you are using.
Flashpoints and Fragrance Strength
Heating a fragrance oil beyond its flashpoint won't make it burn off or lose scent. Flashpoint is a legal term unrelated to fragrance performance. Some misunderstandings stem from the term "vapor" in the flashpoint definition, leading to confusion about fragrance strength when adding to hot wax.
Flashpoints and Transportation
The main concern with flashpoints is actually related to shipping, and air transport safety regulations.
Flashpoints matter because they determine which substances can be safely transported by air. Legally, flashpoint refers to the minimum temperature at which a liquid emits vapor in sufficient concentration to form an ignitable mixture in air near its surface. While the likelihood of a flammable liquid encountering an ignition source during air transit is low, regulations restrict the air transport of liquids with flashpoints at or below 141°F due to safety concerns.
Understanding flashpoints helps ensure safe handling and transportation of fragrance oils, but for candle makers, it primarily impacts purchasing and shipping decisions rather than actual candle-making practices.