John Neeft Netherlands Energy Research Foundation (ECN) Dear John, There is a real easy way to measure tar content in a no pressure drop or collection media process. It can even measure molecular weight, boiling point, and other factors in the gas stream very accurately. I would be willing to discuss it under a confidentiality agreements. Prototype would be easy to build. Tom Taylor The Gasification List is sponsored by USDOE BioPower Program http://www.eren.doe.gov/biopower/ and PRM Energy Systems http://www.prmenergy.com Other Sponsors, Archives and Information http://www.crest.org/renewables/gasification-list-archive http://solstice.crest.org/renewables/biomass-info/gasref.shtml http://www.crest.org/renewables/biomass-info/ http://www.crest.org/renewables/biomass-info/carbon.shtml