A mathematical expression for describing the efficiency of sampling by diffusion in an annular denuder has been derived theoretically from Fick's law of diffusion. Input parameters for the calculation procedure are the tube geometry, flow velocity and the diffusion coefficient of the respective sampled gas. Results from the calculation procedure were compared with existing experimental data on the sampling efficiency of annular denuders indicating a general agreement of calculated and measured sampling efficiencies. © 1989.
Winiwarter, W. (1989). A calculation procedure for the determination of the collection efficiency in annular denuders. Atmospheric Environment (1967), 23(9), 1997–2002. https://doi.org/10.1016/0004-6981(89)90526-X