Table 1.
Previous studies involving ENDS topography measurements.
Fig 1.
Wireless Personal Use Monitor (wPUM) with various commercially available ENDS.
The wPUM is designed with an aperture that can accommodate a variety of ENDS and conventional cigarettes. The wPUM records digitized signals at the rate of 40 samples/sec to the memory of the device.
Fig 2.
Forty-seven individuals responded to the initial recruitment. Data for all twenty participating participants are reported in this study. No participants who participated are excluded from the data presentation.
Table 2.
Participant information collected during the enrollment interview.
Table 3.
Preliminary Data Integrity Analysis for participants 1 through 20.
Fig 3.
Exemplar puffing profiles for participants 1 through 10.
Each panel presents analysis results of a single exemplar puffing session selected from among 7 days of natural use enviroment ENDS puffing sessions by a single participant. The plots in each panel illustrates the mean puff flow rate, puff start time and puff end time as a function of time since the beginning of the puffing session.
Fig 4.
Exemplar puffing profiles for participants 11 through 20.
Each panel presents analysis results of a single exemplar puffing session selected from among 7 days of natural use enviroment ENDS puffing sessions by a single participant. The plots in each panel illustrates the mean puff flow rate, puff start time and puff end time as a function of time since the beginning of the puffing session.
Fig 5.
Cumulative volume inhaled during exemplar puffing sessions shown in Fig 3 for participants 1 through 10.
Each panel presents analysis results of a single exemplar puffing session selected from among 7 days of natural use enviroment ENDS puffing sessions by a single participant. The plots in each panel illustrates the cumulative volume inhaled by the participant with each subsequent puff during the session.
Fig 6.
Cumulative volume inhaled during exemplar puffing sessions shown in Fig 4 for participants 11 through 20.
Each panel presents analysis results of a single exemplar puffing session selected from among 7 days of natural use enviroment ENDS puffing sessions by a single participant. The plots in each panel illustrates the cumulative volume inhaled by the participant with each subsequent puff during the session.
Fig 7.
Frequency distributions of puff duration variation for participants 1–9.
Each frequency distribution panel presents the variation of puff duration of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment.
Fig 8.
Frequency distributions of puff duration variation for participants 10–18.
Each frequency distribution panel presents the variation of puff duration of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment.
Fig 9.
Frequency distributions of puff duration variation for participants 19–20.
Each frequency distribution panel presents the variation of puff duration of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment. The right column panel presents puff duration variation for the entire cohort of 20 participants.
Fig 10.
Frequency distributions of puff flow rate variation for participants 1–9.
Each frequency distribution panel presents the variation of puff flow rate of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment.
Fig 11.
Frequency distributions of puff flow rate variation for participants 10–18.
Each frequency distribution panel presents the variation of puff flow rate of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment.
Fig 12.
Frequency distributions of puff flow rate variation for participants 19–20.
Each frequency distribution panel presents the variation of puff flow rate of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment. The right column panel presents puff flow rate variation for the entire cohort of 20 participants.
Fig 13.
Frequency distributions of puff volume variation for participants 1–9.
Each frequency distribution panel presents the variation of puff volume of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment.
Fig 14.
Frequency distributions of puff volume variation for participants 10–18.
Each frequency distribution panel presents the variation of puff volume of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment.
Fig 15.
Frequency distributions of puff flow rate variation for participants 19–20.
Each frequency distribution panel presents the variation of puff volume of a single participant across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment. The right column panel presents puff volume variation for the entire cohort of 20 participants.
Table 4.
Mean topography characteristics for participants 1 through 20.
Fig 16.
Boxplots of topography characteristic variation between participants 1 through 20.
Each boxplot panel presents the median, 25th percentile lower hinge, 75th percentile upper hinge, 95% confidence interval on the median notch, and outliers beyond the upper and lower fence to illustrate the variation of puffing characteristics between 20 participants across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment. The left panel presents puff duration, the middle panel presents puff flow rate, and the right panel presents puff volume. Individual standard deviations were used to calculate confidence intervals.
Fig 17.
Interval plots of topography characteristic variation between participants 1 through 20.
Mean puff duration sorted from smallest to largest with 95% confidence interval around the mean for 20 participants across multiple puffing sessions conducted during 7 days of ENDS use in the natural use enviroment. The left panel presents puff duration sorted from shortest to longest mean, the middle panel presents puff flow rate sorted from shortest to longest mean, and the right panel presents puff volume sorted from smallest to largest mean. Individual standard deviations were used to calculate confidence intervals.
Table 5.
Cumulative ENDS use and e-liquid aerosol exposure for participants 1 through 20.
Table 6.
Representative puff topography ranges observed in a sample of young adults using their preferred disposable ENDS.