In this work, we present a pressure modulation method developed to study surface effects in hydrogen permeation through iron base alloys. The technique involves the generation of a sinusoidal hydrogen pressure on the input side of a permeation membrane and the measurement of the corresponding sinusoidal hydrogen flow, as an electrochemical current, at the exit side of the membrane. The obtained transfer function depends on both the bulk properties of the permeation membrane and the surface effects at the input and exit sides. By choosing appropriate membrane thickness and material, surface effects are rate determining and can be characterised. Studies of the effect of different Pd films electrodeposited on the input side of the permeation membrane show that there is a finite resistance for the transfer of hydrogen across the hydrogen/palladium interface.