The abundances and distributions of organic constituents in coal smoke particulate matter are dependent on thermal combustion temperature, ventilation, burn time, and coal rank (geologic maturity). Important coal rank indicators from smoke include (1) the decreases in CPIs of n-alkanoic acids, UCM and phenolic compounds with increasing rank, and (2) the increase in the homohopane index [S/(S + R)] with increasing rank. Coal smoke emissions may be identified in atmospheric samples by (1) the unresolved to resolved component ratios (U/R), (2) the distributions and abundances of aromatic molecular markers, specifically picene, alkylated picenes and alkylhydropicenes, (3) the 17 alpha(H),21 beta(H)-hopane to 22R-17 alpha(H),21 beta(H)-homohopane ratio (range 0.05-0.35), and (4) the presence of other source-specific molecular markers. (C) 2000 Elsevier Science Ltd. All rights reserved.