Vaping devices are complex electronic systems that carry genuine fire and explosion risks. The danger does not come from the simple act of vaporization, but from the energy source required to power the device. Understanding the difference between how the liquid and the battery behave under stress is important for assessing the overall safety of these products. Most incidents are linked to a single, high-power component that, when compromised, can fail catastrophically.
Do Vaping Liquids Ignite Easily?
The liquid used in a vaping device, often called e-liquid, is classified as a combustible material, not a highly flammable one. This distinction is based on the flashpoint, the temperature required for the substance to produce enough vapor to ignite in air. Highly flammable liquids, like gasoline, have flashpoints well below room temperature.
E-liquids are primarily composed of Propylene Glycol (PG) and Vegetable Glycerin (VG). PG has a flashpoint around 99°C to 107°C (210°F to 225°F), requiring significant heat before posing a fire risk. VG’s flashpoint is even higher, typically ranging from 160°C to over 175°C (320°F to 347°F). These high temperatures mean the liquid is highly unlikely to spontaneously ignite under normal conditions.
The heating elements inside a vape device operate below these flashpoints to create vapor, not combustion. For the liquid to catch fire, it would need prolonged exposure to an external heat source far exceeding the device’s normal operating temperature. If a fire occurs, it is usually initiated by a separate, much hotter component within the device.
The Primary Danger: Internal Battery Failure
The overwhelming cause of severe fire and explosion incidents involving vaping products is the failure of the lithium-ion battery. These batteries hold a large amount of energy in a small space, making them susceptible to a rapid, self-sustaining reaction called “thermal runaway” if their internal structure is compromised. Thermal runaway occurs when the battery’s internal temperature rises uncontrollably because the heat generated by chemical reactions exceeds the rate of heat dissipation.
This chain reaction is often triggered by mechanical damage, electrical abuse, or internal defects. A common cause is a short circuit, which happens if a loose battery contacts metal objects like keys or coins in a pocket. Physical damage, such as dropping the device, can also damage the thin internal separator, leading to an internal short circuit and subsequent thermal runaway.
Overcharging the battery beyond its specified voltage limit is another form of electrical abuse that destabilizes the battery’s chemistry. Once thermal runaway begins, the battery rapidly vents hot, flammable gases and can forcefully explode due to intense pressure buildup. This explosive force and the resulting high-heat fire cause the most serious injuries and property damage.
Preventing Fire and Explosion Risks
Mitigating fire and explosion risk centers entirely on the proper handling and maintenance of the lithium-ion battery.
Charging Practices
Users should only use the charger specifically provided by the manufacturer, as incompatible chargers can lead to overcharging and battery stress. It is important to avoid charging the device overnight or leaving it unattended for long periods.
Storage and Inspection
When carrying spare batteries, they must never be stored loose in a pocket, purse, or bag where they could contact metal items. Dedicated, non-conductive plastic cases should be used to protect the battery terminals from short-circuiting. Users should also regularly inspect their batteries for signs of damage, such as dents, punctures, or tears in the protective wrap, and replace any compromised batteries immediately. Storing the device and spare batteries away from extreme temperatures and direct sunlight reduces the chance of spontaneous thermal failure.