The kinetics of hydrogen isotopic exchange over fiberglass materials and reference samples (SiO2, H3PO4/SiO2, and HZSM-5) was studied at 500 degrees C under the dynamic adsorption-desorption equilibrium. The concentrations and H/D-exchange rates of different Bronsted acid sites (BAS) were determined using the numerical modeling of isotope exchange dynamics. The correlation between H/D-exchange rate of reference samples and their acidity determined by FTIR spectroscopy of adsorbed CO was established. Based on this correlation, the strength of BAS in fiberglass materials was shown to be comparable to that of HZSM-5 zeolite. (C) 2009 Elsevier B.V. All rights reserved.