The Formulation and Performance of Two Adsorption Models, the Brunauer, Emmett and Teller (BET) and the Dubinin and Radushkevich (DR), Are Compared. Surface Areas of Several Carbonaceous Samples (Coals and Chars) Were Determined by Applying Both the BET and DR Models to Data Obtained When Adsorbing Carbon Dioxide at 273 K. Sensitivity Analyses Indicate that the DR Model Should Have Less Propagation of Error from Experimental Measurements. However, the 'goodness of Fit' of the Experimental Data Tested Indicated that the BET Model Correlated the Data Better. Both Adsorption Models Correlated the Experimental Data Well (R2 > 0.9), Although the BET Model Consistently Gave a Better Fit to the Data. © 1992.