The expansion of the light scattering phase matrix elements over the generalized spherical functions is performed in order to determine the number of the expansion terms providing the representativity of calculational data in the problems on the transfer of polarized light. The expansion coefficients have been investigated assuming typical models of continental and urban aerosol. The model aerosol polydispersions involve, in certain proportions, such components as dust particles (insoluble in water), soluble particles, and soot particles. The data on the convergence of the diagonal and offdiagonal elements of the scattering phase matrices are presented.