The effect of surfactants on surface instabilities of thin liquid film flow on a rotating disk was studied at different flow rates Q (0.5 less than or equal to Q less than or equal to 2 ml/s), rotation rates f (33 less than or equal to f less than or equal to 100 Hz), and volume concentrations rho(s) of the surface active protein BSA (10(-4) less than or equal to rho(s) less than or equal to 4 x 10(-4) wt%) in the far field of large radii r (11 less than or equal to r less than or equal to 25 cm). With these parameters, ranges of the Reynolds number Re (0.48 less than or equal to Re less than or equal to 4.3), Weber number We (22.3 less than or equal to We less than or equal to 1,410), and surface elasticity numbers zeta or E (0.02 less than or equal to zeta less than or equal to 62; 0.1 less than or equal to E less than or equal to 1.4) were covered. The ratio Re/Re-crit varied between values much less than 1 and 15,000. Surface waves were induced with a constant gas jet directed onto the rotating liquid film in order to investigate their propagation velocities. Measured data are in fairly good agreement with linear and nonlinear theories. The damping effect of surfactants was studied using self-excited waves. It could be shown that the adsorbing monolayer is not in thermodynamic equilibrium at small radii r, but approaches equilibrium at larger r. Assuming the validity of linear stability theory with respect to wave damping, the adsorption kinetics of BSA on the flowing film could be traced. The determination of the transition radius from wavy to smooth film surfaces provides a tool to estimate local film pressures in situ. (C) 2003 Elsevier Science (USA). All rights reserved.