Filter/dilution tunnel. A smoke sample is drawn through a tube exactly where it is diluted with air, the ensuing smoke/air mixture is then pulled through a filter and weighed. This can be the internationally identified way of measuring smoke from combustion.[sixty six] 1600 – Tobacco employed as dollars-crop – https://broadfar.com/oraco-pioneering-a-smokeless-future-with-innovative-nicotine-delivery/