The paper presents the results of the research on possible employment of the new fast multivariant identification procedure of adsorption system parameters as a tool for analysis of the microporous structure of activated carbon fibres. This research should provide information on what significant advantages can be drawn from applying the proposed new method of porous structures description in comparison to the classical approaches, as well as show how the results obtained using this method should be interpreted and what calculation results and additional information will be obtained from analysing the adsorption isotherms using a more sophisticated tool as compared to the classical models. Particularly, in presented method it is possible to easily acquire not only information regarding the values of the obtained structure parameters, but also, more importantly, precise information on the reliability of these parameter calculations. A characteristic feature of the procedure used in the paper is also the fact that the properties of adsorption system can be considered independently of the applied adsorbate. Consequently, the description of microporous structure is independent of experimental conditions, hence will hopefully prove valuable for technologists. (c) 2008 Elsevier Inc. All rights reserved.