Adsorption material is widely used to remove gas phase indoor air pollutants such as volatile organic compounds. The commonly used parameter, the adsorption capacity, is not sufficient to determine how much of a gas phase pollutant can be removed in a given time period. In this study, we put forward a new parameter (
, the normalised volume of air cleaned) and an approach to select the most suitable adsorption material for given conditions. We find that
of a single adsorbent pellet is the function of the Biot number for mass transfer (Bim), the air–adsorbent interface partition coefficient (K) and the Fourier number (Fom). The correlation between them is derived, which enables us to determine the most suitable adsorption material under given conditions. The
of a fixed-bed air filter is also presented, from which the required quantity of material or the filter size can be determined too. Some examples illustrating how to use the parameter and the approach are presented. This new parameter and approach are very helpful for selecting adsorption materials and developing adsorption filters for removing gas phase indoor air pollutants.