Filter/dilution tunnel. A smoke sample is drawn through a tube wherever it can be diluted with air, the resulting smoke/air combination is then pulled through a filter and weighed. Here is the internationally identified way of measuring smoke from combustion.[sixty six] Narrowed blood vessels in the placenta and umbilical https://nmate60135.tinyblogging.com/not-known-factual-statements-about-cigarettes-77281451