Cannabis vaping & vaporizer — knowledge hub

Vaporising instead of burning: what happens physically

When burning a joint, temperatures exceed 600 °C. This produces pyrolysis products — tar, carbon monoxide, polycyclic aromatic hydrocarbons — which have nothing to do with the active ingredient but account for the majority of the respiratory burden. A vaporiser operates in the range of about 170 to 210 °C, thus remaining below the combustion threshold: cannabinoids and terpenes transition into the gas phase, and the plant material does not char.

This explains the two practical differences that switchers notice immediately. Firstly, the vapour is significantly less irritating because the particulate load is lower. Secondly, the effect profile shifts with temperature: at lower temperatures, volatile terpenes and the aroma dominate; at higher temperatures, more cannabinoids are released, but the aroma flattens out. Those who dose consciously start low and increase step by step.

Vaporising is therefore the lower-risk, not the risk-free form of consumption. The strain on the respiratory tract decreases, it does not disappear — and the onset of action is just as rapid as with smoking, which, unlike with edibles, keeps the risk of overdosing low.

• Conduction: material lies directly on the heating surface — fast start, less even, stirring required
• Convection: hot air flows through the material — more even, truer flavor, more expensive
• Hybrid: combination of both principles, found in most mid-range devices today
• Starting point for flowers: 180 °C, increase in 5-degree increments, maximum 210 °C

Devices, cartridges and what applies in Switzerland

For flower vaporizers, the same legal situation applies as for the flower itself: freely saleable under 1 % total THC, anything above is a narcotic. The decisive factor is always the total THC, i.e. THC plus THCA multiplied by the factor 0.877. A product with 0.4 % Delta-9-THC and 0.9 % THCA has around 1.19 % total THC and is therefore a narcotic — even if the packaging says «under 1 %». The device itself is a neutral object and is under no circumstances prohibited.

With pre-filled cartridges, the duty of care is higher. The EVALI outbreak in the USA in 2019/2020 was traced back to vitamin E acetate as a cutting agent in unregulated THC cartridges and caused fatalities. The consequence for Switzerland: cartridges only from a traceable source, with a certificate of analysis showing cutting agents and residual solvents. Cartridges from the grey market or from abroad without a test report are the riskiest cannabis product of all — far riskier than the flower itself.

For road traffic, the method of consumption makes no difference. The detection limit of 1.5 µg/L THC in the blood applies; anyone who exceeds this is considered unfit to drive — regardless of whether it was smoked, vaporized or ingested.

How to find the right page in the cluster

The subpages cover device types, temperature control, cleaning and maintenance, the health comparison to smoking, as well as cartridges and their risks. Anyone looking to buy a device should start with the conduction/convection comparison; those who already own one and want to get more out of it should start with temperature control and maintenance.

Cleaning is almost always underestimated: residues in the vapor path noticeably alter the flavor within a few weeks and are the most common reason why users believe their device's performance has declined.

Swiss pilot trials and medical vaping in focus

Since the legal liberalisation in August 2022, medical cannabis in Switzerland has been directly prescribable by doctors without a BAG exceptional permit. For patients, vaporising flowers is the preferred method of inhalation, as it enables a rapid effect without burdening the respiratory tract with combustion products. Vaporising also plays a central role in harm-reduced consumption in ongoing Swiss pilot trials such as Züri Can or Weed Care Basel. The quality-tested flowers distributed there are excellently suited for precise thermal extraction in certified medical vaporisers approved by Swissmedic as medical devices.

In contrast to the unregulated market, the pilot projects and medical sourcing offer the major advantage of standardisation. Consumers know exactly how high the THC and CBD content is, which makes dosing in the vaporiser extremely precise. Anyone vaporising within the framework of these projects or with a prescription also avoids the legal risks of illicit acquisition. Although the cantons enforce the rules differently, possession of medically prescribed cannabis or participation in an official pilot trial protects against the usual fixed penalty fines, as long as the official documents and containers are carried.

• Medically prescribed cannabis may be legally vaporised in certified vaporisers.
• Pilot trials in cities like Zürich and Basel promote vaping as a lower-risk form of consumption.
• Quality controls by the BAG guarantee contaminant-free flowers without pesticides or heavy metals.
• Medical vaporisers are subject to strict Swissmedic guidelines for patient safety.

The Art of Filling: Grind Size and Packing Density

The efficiency of a vaporiser stands and falls with the preparation of the plant material. Unlike rolling a classic joint, an even grind is crucial when vaporising. The flowers should be shredded with a grinder to maximise the surface area without pulverising the material. If the herb is too coarse, the heat does not penetrate to the core; if it is too fine, the device's screens clog, blocking the airflow. The optimal consistency resembles coarse sand, allowing the hot air to flow evenly through the material.

The packing density must also be precisely matched to the device's heating system. Conduction devices require a relatively tight pack, as heat is transferred through direct contact from wall to wall. Convection vaporizers, on the other hand, work with a hot airflow and require a loose pack so that the air can circulate freely. A common practical error is overloading the chamber, which leads to incomplete vaporization. Stirring the material briefly halfway through the session ensures an even thermal extraction of all active ingredients.

• A medium grind maximizes the surface area for an efficient release of terpenes.
• Gently pack conduction vaporizers to optimize physical heat contact.
• Fill convection models loosely to avoid blocking the airflow.
• Stirring briefly during the session noticeably increases the yield of active ingredients.

Economics of Vaping: Initial Costs versus Efficiency

Purchasing a high-quality vaporizer initially requires a significant investment, which, however, pays off in the long run. Compared to combustion, thermal extraction in a vaporizer is many times more efficient. With classic smoking, a large proportion of cannabinoids is lost unused due to the extremely high heat of the embers or is lost in sidestream smoke. A vaporizer, on the other hand, makes optimal use of the loaded plant material, as the active ingredients are vaporized in a targeted manner and inhaled directly. Many consumers therefore report a significantly lower monthly flower consumption with the same intensity.

Another economic and ecological aspect is the reuse of already vaporized material, often referred to in technical jargon as AVB (Already Vaped Bud). Since not all active ingredients are completely dissolved when vaporizing below 210 °C, a residual amount of cannabinoids remains in the brownish plant material. This is already decarboxylated, i.e. activated, by the heat and can be reused for the production of extracts or in the culinary field. This dual use maximizes the value of the raw material and drastically reduces ongoing costs for consumers.

• High initial costs pay off quickly due to the reduced flower requirement.
• No loss of active ingredients through combustion or unused sidestream smoke.
• Already vaped buds (AVB) contain residual active ingredients and can be reused in many ways.
• Durable devices with replaceable batteries lower long-term maintenance costs.

Distinction from e-cigarettes and the risks of liquid vapes

In the public debate, dry herb vaporizers are often mistakenly equated with e-cigarettes. Technically and health-wise, however, there are fundamental differences. While herb vaporizers heat pure, untreated flowers, e-cigarettes and e-vapes are based on liquids, so-called liquids. These usually consist of propylene glycol, vegetable glycerin, and artificial flavorings in which cannabinoids are dissolved. The health risks of heated carrier substances and flavorings are the subject of intensive research, which is why vaporizing pure flowers is considered the cleaner and more transparent method, as no additives whatsoever are inhaled.

Particular caution is advised with pre-filled THC cartridges from the grey market. Since these are often produced abroad without state control, there is a risk of contamination with heavy metals or prohibited cutting agents. Anyone wishing to play it safe in Switzerland should either exclusively use dry herb vaporizers with legal CBD flowers or obtain medical cartridges from official pharmacies. In the event of health complaints or suspected poisoning from inferior liquids, Tox Info Suisse offers free, expert advice 24/7 on the telephone number 145.

• Dry herb vaporizers use pure flowers without any chemical carrier substances or flavorings.
• E-cigarettes vaporize synthetic liquids, the long-term effects of which are still insufficiently researched.
• Illegal cartridges pose high risks due to uncontrolled cutting agents and heavy metals.
• Tox Info Suisse (emergency number 145) helps in cases of poisoning symptoms caused by contaminated vapes.

FAQ