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Show International Flame Research Foundation 1998 Flame Research Committee 11-15 October 1998 The target toxic compounds included and the test methods used are listed below: Target Compounds Test Method Benzene, toluene, ethylbenzene, CARB-410A and xylene isomers (BTEX) Polycyclic Aromatic Hydrocarbons (PAHs) CARB-429 Formaldehyde and acetaldehyde CARB-430 Hie source testing for air toxics were conducted simultaneously with the measurement of criteria pollutants and other combustion gases (i.e. SO^/NOx/CO/THC/O^/CO:) using S C A Q M D Reference Method 100.1. The test methods used and sampling duration was designed to provide extremely low detection limits for all target analytes. Where testing found non-detectable amounts in some runs, emissions factor was derived by assigned a value of half of the detection limit to the non-detect. All analyte concentrations were reported either as parts per billion on a volume basis (ppbv), or as compound weight (in nanograms or milligrams) per dry standard cubic foot (ng/DSCF or mg/DSCF). These results were then normalized to gas flow and the heat content of the fired fuel. The resultant emissions factors are presented in pounds per million British Thermal Units (Lbs./MMBtu) in order to make them comparable to other values cited in the literature, and enable their generalization to other similar units. Table 1 provides the results of the testing. Table 2 provides the range of the resultant Emission Factors for the tested process heaters. All target compounds are included, and those that are not expected to be present, based on triplicate non-detects, are indicated by zeros. The table also lists the corresponding emissions factors for gas-fired external combustion devices (process heaters and boilers) from the recently issued API/WSPA Database (API Publication 348, August 1998), and selected W S P A , 1992 Pooled Source Data The resulting emissions factors for individual compounds in the PAH family, as well as the total P A H s are quite consistent between the current set of test results and those compiled in the 1998 API/WSPA Database. The same is true for the formaldehyde and acetaldehyde results. Only the benzene, toluene and xylene compounds show about an order of magnitude discrepancy, which is hard to explain. This is further confirmation that earlier W S P A Pooled Source Testing data (WSPA, 1992) had erroneous values for PAHs. Those earlier data were taken using a test method that was still evolving at the time, and suffered from major "high blank" values of the absorption media. 3 |