Nominal Operating Envelope of Pod and Pen Style Electronic Cigarettes

Abstract

Many Electronic Nicotine Delivery Systems (ENDS) employ integrated sensors to detect user puffing behavior and activate the heating coil to initiate aerosol generation. The minimum puff flow rate and duration at which the ENDS device begins to generate aerosol are important parameters in quantifying the viable operating envelope of the device and are essential to formulating a design of experiments for comprehensive emissions characterization. An accurate and unbiased method for quantifying the flow condition operating envelope of ENDS is needed to quantify product characteristics across research laboratories. This study reports an accurate, unbiased method for measuring the minimum and maximum aerosolization puff flow rate and duration of seven pod-style, four pen-style and two disposable ENDS. The minimum aerosolization flow rate ranged from 2.5 to 23 (mL/s) and the minimum aerosolization duration ranged from 0.5 to 1.0 (s) across the ENDS studied. The maximum aerosolization flow rate was defined to be when the onset of liquid aspiration was evident, at flow rates ranging from 50 to 88 (mL/s). Results are presented which provide preliminary estimates for the effective maximum aerosolization flow rate and duration envelope of each ENDS. The variation in operating envelope observed between ENDS products of differing design by various manufacturers has implications for development of standardized emissions testing protocols and data reporting required for regulatory approval of new products.

Proposed Standard Test Protocols and Outcome Measures for Quantitative Comparison of Emissions from Electronic Nicotine Delivery Systems

“…Prior work [ 2 ] described the materials and methods used for gathering experimental data previously reported. Briefly, test specimens were procured for testing 13 pen- and pod-style ENDS products from commercial vendors.…”

“…Supplementary Material S2: Data Availability Statement: Data supporting the results reported herein is provided in the Supplementary Material associated with this article. Additional underlying predicate data reported as supplemental data accompanying reference [2].…”

“…As detailed previously [ 1 , 2 ], no widely accepted puffing topographies or emissions outcome measures have been established for use in ENDS emission studies, although emissions have clearly been demonstrated to be dependent upon usage conditions and product characteristics. A proposed vaping machine standard [ 3 ] does not reflect the range of use behavior associated with product use but offers a consistent foundation for comparative emissions studies between ENDS.…”

“…Product design characteristics describing the 13 ENDS PCUS and corresponding consumable used for this investigation. Adapted from underlying data reported in[2].…”

“…Power was not experimentally measured in this investigation. Maximum nominal power was, for relative comparison only, computed from P Nom = V2 Nom /R Coil where V Nom was set to a constant value of 3.3[VDC].…”