Parameter uncertainty is taken into account in the evaluation of a multitubular fixed-bed catalytic reactor design. It concerns the conversion of CFC based on laboratory observations. Uncertainty analysis based on sensitivity analysis of a reactor model is carried out to evaluate reactor operability and to deal with the parameter uncertainty. The theory and practical implementation of a linear (direct differential method) and a non-linear (Fourier Amplitude Sensitivity Test) technique for sensitivity analysIS re presented. The sensitivity techniques have been implemented in an equation-oriented software environment, which simultaneously solves all differential and algebraic equations. Both sensitivity techniques are illustrated for and compared with a non-linear analytical function and applied in the uncertainty analysis of the reactor model. Correlation information between the uncertain parameters has been included in the analysis.