Filter/dilution tunnel. A smoke sample is drawn through a tube the place it is actually diluted with air, the resulting smoke/air combination is then pulled through a filter and weighed. This is the internationally acknowledged way of measuring smoke from combustion.[66] Very little smoke is produced at this stage. https://nuso56677.wikinewspaper.com/3623627/helping_the_others_realize_the_advantages_of_tabacco