TPM – The New Criteria to Choose A Good E-cig

What are the criteria for a good e-cig? People used to rely on some subjective opinions such as KOLs’ reviews to choose their vaporizers, are there more objective criteria to do that? This article introduces TPM and explains how it helps us to assess a good vape device.

1. What is TPM?

TPM is short for Total Particulate Matter. It represents the sum of all solid and liquid particles suspended in a vape cloud. Similar to the importance of PM2.5 in measuring air quality, TPM is an irreplaceable index in smoke quality testing.

As we all know, it is hard to quantify smoke level/dose with naked-eye observation. However, TPM measurement makes smoke quality become visualizable and measurable, and it can be further utilized in analyzing the chemical and physical properties of the smoke.

Also, TPM testing results provide a basis for research in environmental engineering and pathology. This is also the reason why TPM is seen as ‘a golden key for vaping technology’.

2. The application of TPM

‘A golden key can open any door.’ TPM is generally applied by many organizations in different industries. For instance, a study from WHO (World Health Organization) (2018) mentioned that

‘A review of WHO SOP-03 for TSNAs(Tobacco-specific nitrosamines) in mainstream tobacco smoke suggests that the chemistry of ENDS aerosol is compatible with the WHO SOP and that either aerosol TPM collected on CFPs(Cambridge filter pads) or e-liquid could be analysed.

As noted above, however, the reported levels of TSNAs in ENDS aerosol are below the reporting limit of the WHO SOP for TSNAs in tobacco smoke. ’

TPM is an international standard in the tobacco industry, and it is also applied to tests for e-cig commonly. To ensure the universality of the ‘golden key’, several specifications were set for different aspects, including smoking simulation, sampling methods, and experimental environments.

A TPM report of SLIMO™ vape devices (a new generation product from ALD Group Limited) is quoted in the article to explain TPM more clearly.

3. TPM and Puff Volume

Producing massive and stable vapor is the basic requirement for an excellent vape device. TPM (mg/puff) can reflect the puff volume of a vaping device.

Below Figure 1 shows the differences in puff volume between SILMO™ devices and other vaporizers.

Notes：

• TPM(mg) on a vertical axis stands for puff volume
• Puffs on the horizontal axis stand for the number of puffs
• As shown in the chart, the TPM value ofSLIMO™ devices stays steady between 6-7mg, while that of the contrasted devices is lower-lying between 3.5-5mg.
• That is to say, in a single puff, the puff volume of SILMOTM device is 1.5-2 times that of other ordinary devices.
• What’s more, the higher the number of puffs, the bigger disparity of puff volume.

4. TPM and Device Lifespan

Smoke simulation tests are conducted on the devices in the report. The test results bring out something new, such as the relationship between lifespan and heating coil.

Usually, the unstable vape performance of electronic cigarettes is caused mainly by the short lifespan of its heating coil. It is also the main reason for burnt taste, spit-back, and even not working. If vape devices that are applied the same heating coil have well performance in experiment, taste consistency and stability of this batch of products can be ensured.

Figure 2 illustrates TPM testing results under 500 puffs simulation.

Notes：

• TPM(mg) on the vertical axis stands for puff volume
• Puffs on the horizontal axis stand for the number of puffs

After 500 puffs under the same conditions, the SILMO™ device performs steadily in the terms of puff volume.

However, the contrasting device performs well in the beginning while creates less and less puff volume even stops working finally.

5. TPM and Safety

It is the most important thing to make sure electronic cigarettes not release harmful substances over the standard when using.

With TPM, it is feasible to conduct some tests and analyses on the safety of e-cigarettes, for example, carbonyl compounds testing, the test items of which include formaldehyde, acetaldehyde, and acrolein.

The limits required by European Union Tobacco Products Directive (TPD) for formaldehyde, acetaldehyde, and acrolein in a single e-cig are as follows:

Let’s look at how SILMO™ device performs

Note:

• μg/200puffs on vertical axis stands for the μg of aldehyde per 200 puffs
• Horizontal axis shows different devices, the bigger scatter, the denser data.

We can find in the above charts:

• The test results for formaldehyde and acetaldehyde of all tested devices are compliant with the requirements of TPD.
• The μg of acrolein released bySILMO™ devices is far lower than the limit of TPD, while some results of contrasted devices fail to meet TPD requirements.

6. Conclusion

TPM shows us three important criteria of vaping technology:1. Puff Volume, 2. Safety, 3. stability

With TPM, vape manufacturers know how to produce vape products, and consumers know how to check the performance and safety of a vape device.

According to the above TPM tests, we know vape devices utilized different heating elements perform differently. Devices powered by SILMO™, a heating element technology developed by ALD Group Limited, perform excellently in the tests.

TPM test has to be conducted under strict experimental conditions. Besides, its testing devices are costly, so only top laboratories and research institutions can afford it. For e-cig users, it is not realistic to review a vape via TPM. However, we believe that as the industry becomes more and more standardized and transparent, the TPM test will be applied to a wider range, including choosing an e-cig.