The present invention relates to a barrier membrane arrangement(10, 110) for a medical device for providing a substantiallyliquid 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 firstand a second medical device at the barrier member arrangement (10,110). The barrier member arrangement (10, 110) comprises a firstmember (11), a second member (13) and a barrier member (12). Thesecond member (13) can be interlocked to the first member (11) bymeans 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 increasedleakage 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).
