Smoking topography was assessed in a smoking chamber with a chimney vent. Participants were asked to smoke a cigarette of their own brand ad libitum. The cigarette is attached to a sterilized flow-meter mouthpiece that runs through a pressure transducer. The pressure transducer is connected to a computer that translates the puffing measures into stored data (Clinical Research Support System, Plowshare Inc., Baltimore, MD). Vital signs (heart rate, blood pressure and pulse oximetry) were measured prior to smoking and immediately after smoking. Smoking sessions averaged 25 minutes in duration. The 25 minutes included the requisite safety observation time, some acclimation to the smoking chamber to enhance the validity of the smoking measures, as well as a measure of vital signs before and after the smoking session.
