CBD dabs: equipment, measured temperatures and French law
Dabbing means putting a hemp concentrate on a very hot surface and inhaling the vapour through a water pipe known as a rig. Users report surface temperatures of 340 to 482 °C; the flower vaporisers studied run at 185 to 210 °C. Phytogrammes sells no concentrate meant for dabbing and no dabbing equipment.
Key takeaways
- Dabbing names a way of heating, used on concentrates and never on flower or pressed hash.
- Four parts make up the kit: the rig, the nail, the cap and a heat source, either a torch or an e-nail.
- In a 2017 study, methacrolein was undetectable at 322 °C and reached 131 to 185 ppb between 403 and 526 °C.
- French law regulates the product: 0.30% Δ⁹-THC at most, adults only, and never sold as a food.
What the word "dab" means
To dab is to press lightly, and that is the gesture: a small amount of sticky material goes onto a hot surface. A 2025 review in Frontiers in Toxicology defines dabbing as flash vaporisation on a heated surface.
The word names no product category. What gets heated is a concentrate, such as butane extract, wax, shatter or rosin; dried flower and pressed hash are not used. A "CBD dab" is just this technique applied to a concentrate rich in cannabidiol.
Vaporising flower is a different practice. A vaporiser keeps a chosen temperature for the whole session. A dab works by contact: the surface is heated first, and it cools as soon as the material lands on it. Mechanics and temperature scale both differ between the two.
The equipment, part by part
| Part | Role | What varies between models |
|---|---|---|
| Rig | Water pipe that cools the vapour before inhalation | Volume, type of filtration |
| Nail | Heated surface that receives the concentrate | Material: quartz, ceramic, titanium |
| Carb cap | Covers the surface and lowers the pressure above it | Shape, airflow |
| Torch | Flame heat source, running on butane | No temperature reading |
| E-nail | Heating element driven by a controller | Displayed set point |
According to a 2015 study in the Journal of Toxicological Sciences, the nail is made of quartz, ceramic or titanium and often heated with a blow torch. The 2017 study in ACS Omega adds two items. One is the temperature-controlled e-nail; the other is the carb cap, which lowers the pressure over the surface so the material vaporises at a lower temperature.
The main divide is between flame and heating element. With a torch, the temperature depends on how long you heat, the mass of the nail and how long you wait before the dab, and nothing measures it at the moment of use. An e-nail shows a set point. That figure is what the device regulates, which may differ from what the material meets at the point of contact.
Two temperature scales not to confuse
Standard tables list 157 °C for THC. The figure comes from high-vacuum distillations at 0.05 Torr, in work from 1941 and 1964. At normal pressure, a 2025 study in the Journal of Cannabis Research measured THC's boiling point at about 245 °C. As far as we know, nobody has published the same measurement for CBD. Molecules still evaporate well below their boiling point, as water in a puddle does.
Vaporiser studies mostly use settings between 185 and 210 °C, and combustion begins around 230 °C. Those studies are covered in our guide to CBD vaporisation temperatures.
Dabbing sits higher up the scale. In the 2015 study, the titanium nail was heated for 10 seconds to about 300 °C before 40 mg of concentrate went on. The 2017 authors report that e-nail users quote set points of 340 to 482 °C, often around 378 °C, and that most prefer the higher values so that everything vaporises.
What the heat produces
In the 2017 study, terpenes, the aromatic compounds of hemp, were heated on a ceramic nail and the results extrapolated to a 40 mg dab of extract. The authors measured methacrolein, an irritant compound, in the inhaled air.
| Surface temperature | Methacrolein |
|---|---|
| 322 °C | Not detected |
| 403 °C | 131 ± 9 ppb |
| 455 °C | 157 ± 2 ppb |
| 526 °C | 185 ± 11 ppb |
Benzene showed up only in the hottest range, at about 15 ppb per extrapolated dab. The measurements were made in a laboratory on terpenes alone, with no real dab involved, and they say nothing about health effects. What they do show is that a hotter surface puts more breakdown products into the vapour.
The 2015 study looked at the other end. Up to 40% of the THC theoretically available ended up in the collected vapour. The same study shows why the residual solvents line matters: solvents turned up in 83.3% of the extracts tested and in none of the hash samples. How to read that line is explained in our article on a concentrate's certificate.
Which products are involved, and what Phytogrammes sells
Dabbing uses concentrates that melt without leaving residue: butane extracts, wax, crumble, rosin. The first family is described in our guide to wax and concentrates, the second in the article on rosin. For hash, the full melt grade means a resin that melts entirely under heat, typically collected on the 73 to 90 micron meshes.
In France, a study by addiction-monitoring centres, funded by MILDECA, published in December 2023, analysed 248 CBD products. Contents ranged from trace amounts to 90%, with the highest in concentrated forms such as wax, crystals, crumble and oil. Of the samples, 46% had no composition labelling, and 30 exceeded the THC limit, at 0.4 to 1.2%.
Phytogrammes sells no concentrate intended for dabbing, and no rig, nail or e-nail. Its catalogue covers flowers, oils and resins made without solvent. This article explains a term and gives no instructions for use. Our FAQ collects the compliance questions.
The French legal framework
French law regulates the material that is heated, whatever the device. The decree of 30 December 2021 limits cultivation and sale to Cannabis sativa L. varieties listed in the official catalogues whose Δ⁹-THC does not exceed 0.30%. Its Article 1, III sets the same ceiling for extracts and for products containing them, which includes concentrates.
On 29 December 2022, the Conseil d'État struck down part II of that article, which banned the sale of raw flowers and leaves, holding that a general and absolute ban was not proportionate. The 0.30% threshold stayed the same. These products are reserved for adults and are not foods.
Frequently asked questions
The law looks at the product and is silent on the technique. A hemp concentrate is lawful if the finished product contains no more than 0.30% Δ⁹-THC, the threshold in Article 1, III of the decree of 30 December 2021. You can check it on the batch certificate. Only adults may buy it.
They differ in mechanics and in scale. A vaporiser holds a set point, often 185 to 210 °C in studies. A dab puts the material on a preheated surface, quoted by users at 340 to 482 °C, which cools once the material lands.
That value comes from distillation under vacuum. A 2025 study puts THC's boiling point at about 245 °C at normal pressure. Below that, part of it still evaporates, only more slowly.
No. The catalogue offers flowers, oils and solvent-free resins, with no rig, nail or e-nail and no concentrate such as wax, shatter or rosin.
The figures measure different things. A boiling point describes a pure molecule and changes with pressure. A dab temperature describes a surface, and it depends on the nail, the heating time and the wait before the dab.
Written by the Phytogrammes team
Each journal article draws on cited primary sources: ANSM, EFSA, EUR-Lex and peer-reviewed publications. Product profiles are distinguished from documented laboratory results. Our approach.
Article published on . CBD is not a medicine.