An open-label, single center, three-arm observational study to examine emissions from e-cigarettes versus conventional cigarettes under three environmental settings of typical residential, office and hospitality facilities.

Specific constituents will be measured in exhaled breath samples (EBS) from adult e-vapor product users and smokers when they are using e-vapor products or smoking conventional cigarettes. These constituents and particle counts (PC), will be measured in the room air samples (RAS) collected in the environmental exposure chamber (EEC) where adult e-cigarette users and smokers are using electronic cigarettes or smoking conventional cigarettes.

All subjects will undergo a Screening Visit to assess if they meet study eligibility criteria. If all eligibility criteria are met and the subject signs informed consent, the subject will be assigned to one of three groups: Group I (JUUL), Group II (VUSE Solo), or Group III (Conventional Cigarettes).

All three Groups will be sequentially observed in environmental settings 1 (residential), 2 (office), and 3 (hospitality). The observation period allocated for each environmental setting will be 2-days and 2-overnights for Groups I and II, and 1-day and 1-overnight for Group III. Each observation period will be referred to as a "Clinic Visit".

Subjects will move on to subsequent Environment Settings (Clinic Visits 2 or 3) after completion of the previous Clinic Visit (1 or 2).

Subjects must return to the clinic for Clinic Visit 1 within 60 days of the Screening Visit. Clinic Visit 2 must occur 7 ± 2 days after the Clinic Visit 1, and Clinic Visit 3 must occur 7 ± 2 days after Clinic Visit 2.

Inclusion Criteria:

Subjects must satisfy the following criteria before being enrolled into the study. Subjects must:

1. Be informed of the nature of the study and agree to and are able to read, review, and sign the informed consent document (in English) prior to the first study procedure. The Investigator must be satisfied that the volunteer has the ability to read and communicate in English in order to participate in the study.
2. Subjects screened as a part of an IRB-approved General Screening Protocol at the CRO site may be included in this study without additional Screening procedures provided all the required Screening procedures have been performed within 60 days prior to Clinic Visit 1.
3. Be a healthy male or female volunteer aged 21 - 65 years at the time of Screening Visit.
4. Have a positive urine cotinine result at Screening (Screening Visit) of >200 ng/ml.
5. Be judged by the Investigator to be in good general health as documented by the medical history, physical examination (including but may not be limited to an evaluation of the cardiovascular, gastrointestinal, respiratory and central nervous systems), vital sign assessments, 12-lead electrocardiogram (ECG), clinical laboratory assessments, and by general observations. Any abnormalities or deviations outside the normal ranges for any clinical testing (laboratory tests, ECG, vital signs) can be repeated at the discretion of the Investigator and judged to be not clinically significant for study participation.
6. Agree to abide by the study restrictions and return for the required assessments.
7. Have a self-reported daily conventional cigarette consumption rate of a minimum of 10 cigarettes per day for a minimum of 3 months prior to Screening Visit.

Exclusion Criteria:

Subjects who meet any of the following exclusion criteria will not be enrolled in the study.

Subjects must not:

1. Report receiving any investigational product within 30 days prior to Screening (Screening Visit).
2. Report any presence or history of a clinically significant disorder involving the cardiovascular, respiratory, renal, urologic, gastrointestinal, hepatic, immunologic, hematologic, endocrine, oncologic or neurologic system(s) or psychiatric disease as determined by the Investigator.
3. Have any clinically significant results from laboratory tests, physical examinations, vital signs assessments, and electrocardiograms, as judged by the Investigator.
4. Report a clinically significant illness during the 30 days prior to enrollment, as determined by the Investigator.
5. Report a history of drug or alcohol addiction or abuse within the past 1 year.
6. Have positive screen for alcohol or drugs of abuse at Screening (Screening Visit) or check-in at Clinical Visit 1.
7. Have positive test for human immunodeficiency virus (HIV), hepatitis B surface antigen (HbsAg), or hepatitis C virus (anti-HCV).
8. Have body mass index (BMI) greater than 40 kg/m2 or less than 18 kg/m2 at Screening (Screening Visit).
9. Have used prescription anti-diabetic medication and/or insulin therapy within 12 months of Screening (Screening Visit).
10. Have taken medication for depression or asthma within 6 months of Screening (Screening Visit).
11. Have used prescription or over-the-counter bronchodilator medication (eg, inhaled or oral β-agonists) within 6 months of Screening (Screening Visit).
12. Be breast-feeding or pregnant female subjects (confirmed by a positive pregnancy test). Female subjects, who are considered women of child bearing potential (WOCBP) and sexually active, must be willing and able to use an acceptable method of contraception from Screening (Screening Visit) through the end of the study.
13. Be allergic to propylene glycol or glycerin.
14. Be or have a first-degree relative (ie, parent, sibling or child) be a current employee of the Sponsor or Site.