The present invention relates to a barrier membrane arrangement (10, 110) for a medical device for providing a substantially liquid tight seal between a piercing member and a barrier member (12) and a method for manufacturing such a barrier member arrangement. The present invention also relates to a method for connecting a first and a second medical device at the barrier member arrangement (10, 110). The barrier member arrangement (10, 110) comprises a first member (11), a second member (13) and a barrier member (12). The second member (13) can be interlocked to the first member (11) by means of a connection arrangement (18) at an optional stage by a user. After interlocking the second member (13) to the first member (11), the barrier member (12) has been compressed to provide for an increased leakage security. The barrier member arrangement (10, 110) also provides for a prolonged working life of the barrier member (12) and any medical device which comprises such a barrier member arrangement (10, 110).
