This flowchart is based upon Figure 2 from the following review:
 (May 2014). "Electronic cigarettes: product characterisation and design considerations". Tob. Control 23 Suppl 2: ii4–10. DOI:10.1136/tobaccocontrol-2013-051476. PMID 24732162. PMC: 3995271.
This image was manually redrawn with a few superficial changes relative to the linked figure. It was redrawn in an svg format using inkscape.
Own work based upon [1]
Seppi333