standardised measurement (International Organization for Standardization, 2000) and provides an established platform for comparing emissions from different products. Some scientific and regulatory groups have proposed using two regimes as a means of estimating the lower and upper boundaries of possible emissions from cigarettes: the International Organization for Standardization (ISO) regime, which consists of a 35 mL puff of 2 s duration taken every 60 s (ISO 4387:2000) and a more intense regime