Activating a concentrate vaporizer, or dab pen, when its oil reservoir is empty results in a “dry hit.” This action is considered harmful and produces an intensely unpleasant, burnt taste and a harsh sensation in the throat and lungs. Dab pens are designed to heat viscous oil concentrate for vaporization, not combustion. A dry hit occurs when the heating element is activated without liquid to absorb the heat and produce vapor.
The Mechanism of a Dry Hit
Dab pens rely on concentrated oil to function as a thermal buffer and a medium for vaporization. The heating coil, or atomizer, is typically wrapped around a wicking material like cotton, ceramic, or silica, which draws the concentrate toward the heat source. During normal operation, the liquid concentrate absorbs the coil’s heat, producing smooth vapor.
When the oil is depleted, the wicking material dries out, and the coil is directly exposed to the device’s electrical current. The coil’s temperature rapidly increases far beyond its intended operational range, a process sometimes called thermal runaway. This extreme overheating causes the wicking material and any residual concentrate to combust instead of vaporize. The high heat also begins to degrade the physical components of the atomizer itself.
Health Implications of Inhaling Burnt Material
The extreme heat generated during a dry hit triggers the thermal degradation of materials not meant to be inhaled. The most immediate consequence is inhaling combustion byproducts from the wick. Materials like cotton or silica, when burned, release fine particulate matter and harsh fumes that irritate the respiratory system, causing immediate coughing and throat discomfort.
Chemical Byproducts
The process can create hazardous chemical byproducts from residual concentrate or carrier liquids. Overheating substances like propylene glycol or vegetable glycerin, sometimes used in concentrates, can form carbonyl compounds, including formaldehyde and acetaldehyde. These compounds are known irritants and potential toxins, making the inhalation of a dry hit significantly more concerning than regular vapor.
Heavy Metal Release
A dry hit also risks the release of heavy metals from the heating element itself. Atomizer coils are often made from metal alloys like nickel, chromium, or iron, which are stable at normal operating temperatures. When the coil overheats due to the lack of concentrate, the metal can degrade, potentially releasing microscopic metal particles or metal oxides into the lungs. Studies show that dry hitting conditions significantly increase cytotoxicity compared to normal use, suggesting a greater potential for lung cell damage.
Impact on Dab Pen Hardware
A dry hit causes permanent damage to the dab pen’s internal hardware, specifically the atomizer or coil. When the heating element is activated without liquid, the wick material scorches instantly, becoming brittle and permanently burnt. This burnt residue cannot be removed and will taint all subsequent hits, resulting in a persistent, acrid taste even after refilling the cartridge.
The excessive heat also causes thermal stress and oxidation of the coil’s metal components. This degradation shortens the atomizer’s lifespan and dramatically reduces its performance. Continuing to use a dry-hit coil leads to uneven heating and poor vapor production, often requiring immediate replacement of the cartridge or coil head. The hardware damage represents a financial loss, as the heating element is rendered useless prematurely.
Strategies for Avoiding Empty Hits
Preventing a dry hit requires mindful usage and regular maintenance of the device. The most direct strategy is to consistently monitor the oil level in the cartridge or tank, ensuring the concentrate always covers the wick intake holes. Refilling or replacing the cartridge before it reaches a critically low level avoids coil exposure.
Properly priming a brand new coil is a necessary preventative measure. This involves applying concentrate directly onto the exposed wick material before use and allowing the device to sit for several minutes to ensure full saturation. Paying attention to subtle changes in vapor quality can signal low oil; a noticeable reduction in flavor or decreased vapor density are early warnings to stop use.
Users should also avoid “chain vaping,” or taking rapid, consecutive puffs. This practice can vaporize the concentrate faster than the wick can re-saturate, temporarily creating a dry section on the coil. Allowing short pauses between draws gives the concentrate time to fully soak into the wicking material, maintaining a consistent thermal barrier. Using the lowest effective voltage or wattage setting on the device will also help prevent the coil from overheating too quickly.