Study on the impact of vaporisation regimes

Impact of vaporisation regimes on the efficiency of an electronic cigarette

Study background:

The electronic cigarette is a research subject that is hugely popular in the scientific community. Unfortunately, many studies are carried out in unrealistic ways by research teams. The greatest criticism that can be made is the laboratory use of high-powered equipment, tested with a very low inhalation rate.

Example of unrealistic studies:

A recent publication of November 2019  https://tobaccocontrol.bmj.com/content/early/2019/11/25/tobaccocontrol-2019-055078 tests equipment between 50 W and 200 W recommended for 75 W max with inhalation behaviour close to that of a smoker (low inhalation rate). Their conclusion is that an electronic cigarette burns! Who knew?

Work of the ingésciences team

With its new publication, ingésciences explains that for a given atomiser, there is a good way to inhale.

For this, we demonstrated that for an atomiser with a given power, there is a minimum volume of puff to be respected.  Below this volume, the vapour generated is not sufficiently cleared. Above this volume, it may be considered that all the vapour generated is inhaled.

This puff volume will be different for each atomiser. An atomiser for a beginner will benefit from a low minimum volume compared to atomisers for experienced vapers. The more the delivered power is increased, the more the puff volume has to be increased. This is why high-powered atomisers are used in Direct-to-Lung inhalation. This puff power-volume coupling makes it possible to increase the efficiency of the equipment

Looking at the figures, an atomiser for a beginner vaper will have a minimum puff volume around 50 mL. That of an experienced vaper will approach a volume of 500 mL. These two values are not insignificant as they represent two characteristics of the human body. The first is the volume of the mouth. The second is the volume of air that is breathed whenever one inhales. They correspond to two behaviours of vapers: Mouth-to-Lung (MTL) inhalation vs Direct-to-Lung inhalation (DTL).

By using the puff volume of an experienced vaper, clearance of the vapour is maximised. Atomisers are then more efficient and give more realistic results. It is therefore necessary to adapt inhalation behaviour (puff volume) to the equipment required to be studied.

Involvement:

Thanks to these results, ingésciences is now responsible for drafting the standard on definition of the intense vaping profile (profile used on vaping machines to reproduce the behaviour of an experienced vaper).

Conclusion :

It is crucial to understand the phenomena governing the vaporisation of an electronic cigarette. The work in this ingésciences publication advances Research and provides the scientific community the keys for correctly studying vaping.