Three amorphous glassy polymers (polyetherimide Ultem-1000, polyhexafluoropropylene and poly(3,4-bis(trimethylsilyl) tricyclonon-7-ene) were subjected to different physical treatments (biaxial stretching, removal of residual solvent (drying), annealing, aging, etc.). This work summarizes the observations made earlier in the papers of the same group of authors but also presents some new results. The treatments were shown to produce various changes of gas permeability and diffusivity. In all the cases with good accuracy the diffusion coefficients followed a well-known equation logD= a-b.d(2), here d is the kinetic diameter of gas molecules. The parameters a and b were shown to be sensitive to the treatments of the polymers and, in addition, linearly correlate with each other. By combining equations of Eyring and Meares, it was demonstrated that the parameters a and b can characterize the deviation from equilibrium state of polymers after particular treatment.