The invention relates to a substrate processing apparatus (10) comprising a support frame (60), a radiation projection system (20) for projecting radiation onto a substrate to be processed, a substrate support structure (30) for supporting the substrate, and a fluid transfer system (150). The radiation projection system comprises a cooling arrangement (130) and is supported by and vibrationally decoupled from the support frame such that vibrations of the support frame above a predetermined maximum frequency are substantially decoupled from the radiation projection system. The fluid transfer system comprises at least one tube (140) fixed at two points (151,152), and comprises a flexible portion. A substantial part of the flexible portion extends over a plane substantially parallel to the substrate support structure surface. The stiffness of the flexible portion is adapted to substantially decouple vibrations at the second fixed point which are above the predetermined maximum frequency from the first fixed point.