Plastic scintillation foils of polystyrene and polycarbonate with a thickness between 45 and 200 μm, have been produced using the solvent evaporation method. PSfoils presented a reproducible thickness (10-20%). PSfoils were characterized by the measurement of 36Cl or 241Am. For 36Cl spectrum is located at medium energies since not all energy is deposited in the scintillator and not all betas interact with the foils. For 241Am the efficiency values are very high and spectrum is a sharp peak located at high energies. 222Rn absorption (LD and K) and desorption capacities of the PSfoils have been also evaluated.