84, determined that smoke/aerosol density remained fairly constant while puffing on a traditional cigarette from start to finish approximately 10 puffs, although diversifications did exist among brands of conventional cigarettes. The aerosol density for e cigarettes, while higher than traditional cigarettes in three out of case study solution four brands tested, also remained fairly consistent for case study answer first 10 puffs of a new e cigarette cartridge. However, a decremental reduce in aerosol density was accompanied as each cartridge approached its terminal life. Consequently, this reduce in aerosol density will require case study solution person vaping to generate more vacuum to hold an aerosol density comparable to case study answer initial puffs and will be a reason contributing to longer puff length for electronic cigarettes than for traditional cigarettes 85. Similar variations in case study solution rate of airflow required to supply aerosol between and within brands of e cigarettes were also mentioned by Williams and Talbot 86. According to Goniewicz et al.