Jojoba oil is technically a liquid wax extracted from the seeds of the Simmondsia chinensis shrub. The immediate answer to whether this substance is flammable is no; it is not classified as a flammable liquid under standard regulatory definitions. While it will burn if subjected to extreme heat, its unique chemical structure provides significant stability, making it safe for cosmetic and industrial applications.
Understanding Jojoba Oil’s Chemical Stability
The reason Jojoba oil is not flammable lies in its distinct molecular structure, which sets it apart from nearly all other plant-based oils. Most common vegetable oils, such as olive or sunflower oil, are composed primarily of triglycerides, which are three fatty acid molecules attached to a glycerol backbone. Jojoba oil, however, is composed of over 97% long-chain wax esters, consisting of a single long-chain fatty acid linked to a long-chain fatty alcohol.
This wax ester composition results in exceptional oxidative stability and resistance to high temperatures. The flash point is the minimum temperature at which a liquid gives off enough vapor to ignite temporarily. Jojoba oil’s flash point is remarkably high, approximately 295°C (563°F), indicating it requires significant external heat to produce ignitable vapors.
Flammable Versus Combustible Liquids
The distinction between a flammable and a combustible liquid is based on a regulatory classification system centered on the flash point. According to organizations like the National Fire Protection Association (NFPA), a flammable liquid is one with a flash point below 37.8°C (100°F), and these are categorized as Class I liquids. Flammable liquids produce ignitable vapors at normal room temperature, posing a higher fire risk.
A combustible liquid has a flash point at or above 37.8°C (100°F), requiring substantial heating before a fire hazard exists. Combustible liquids are further divided into Class II and Class III categories. Given Jojoba oil’s high flash point of 295°C (563°F), it falls into the Class IIIB category, which includes liquids with a flash point at or above 93.3°C (200°F).
This classification means that Jojoba oil is a low-hazard combustible material, not a flammable one. The liquid itself does not burn; rather, it is the vapors released when the liquid is heated past its flash point that will ignite. This high heat requirement makes accidental ignition highly unlikely under normal conditions.
Practical Safety and Storage Guidelines
While Jojoba oil is highly stable and classified as a low-hazard combustible liquid, proper storage is necessary to maintain the oil’s quality and prevent degradation. It should be kept in a cool, dark location, away from direct sunlight and extreme heat sources.
Exposure to high heat, such as near a stove or open flame, should be avoided to prevent the oil from reaching its flash point. If the oil is heated for applications like making candles or cosmetics, appropriate ventilation must be used, and insulated gloves are necessary to prevent thermal burns.
Storing the oil correctly protects its long-chain esters from breaking down, which preserves its stability and beneficial properties. Careful storage practices ensure the oil’s quality remains high, leveraging its inherent oxidative resistance and long shelf life.