| Abstract
| - Despite intensive efforts during the past 20 years, nogenerally accepted standard method exists to measureblack carbon (BC) or elemental carbon (EC). Data on BCand EC concentrations are method specific and can differwidely (e.g. Schmid et al., 2001, ten Brink et al., 2004). Inthis study, a comprehensive set of methods (both optical andthermal) is compared. Measurements were performedunder urban background conditions in Vienna, Austria, acity heavily impacted by diesel emissions. Filter and impactorsamples were taken during 3 weeks in summer 2002 andanalyzed for EC with thermal methods: a modified Cachiermethod (Cachier et al., 1989), a thermal-optical method(Schmid et al., 2001), and the VDI method (VDI, 1996); forBC with optical methods: a filter transmission method andthe integrating sphere method (Hitzenberger et al., 1996);and for total carbon (TC) with a combustion method (Puxbaumand Rendl, 1983). The online methods aethalometer(Hansen et al., 1984) and the multiangle absorption photometerMAAP (Petzold et al., 2002) to measure BC were alsoused. The average values of BC and EC obtained with themethods agreed within their standard deviations. Aconversion table was set up to allow comparisons betweendata measured elsewhere under urban backgroundconditions (with similar source characteristics) withdifferent instruments. An approach to estimate the absorptioncoefficient from attenuation data is derived so thatexisting records of aethalometer data in urban environmentsmay be used to obtain also the absorption coefficients.
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