2.2 Selection criteria When drawing up the annual plan and making the concomitant selection of the places to be visited, the following criteria may for instance be used as a basis (the list is not exhaustive): - significance and size of the facility - geographical spread - accommodation of special groups (e.g. migrants, asylum-seekers, the homeless) - special incidents in the recent past - places which are rarely visited because of their geographical location. Furthermore, information from third parties (such as individuals, NGOs, the press) may be considered. Places which were visited recently by the CPT, the SPT or national commissions should not be given priority in order to avoid repeated effort. No. 3 The procedure followed when carrying out a visit 3.1 Announcement of the visit Visits to detention facilities (depending on the facility) shall either be carried out unannounced or with 12-24 hours’ advance notice. To this end, contact shall initially be established with the agreed contact in the Federal Ministry of the Interior or of Defence. Direct contact is then established with the respective head of the facility. In smaller facilities in particular, an unannounced visit can be carried out with no advance notice. Where possible, several unannounced visits should also be carried out in a period under review. Where visits are announced, initial information should be requested on current occupancy, coming deportations, as well as further details that are necessary for preparation (such as whether an interpreter is needed). 3.2 Duration of the visit The duration of the visit depends above all on the size of the facility and the visiting programme. It should be suitable in order to offer the opportunity to talk with all the players involved. It should also be taken into account here that operational procedures may hinder or delay the course of the visit. As a rule, a maximum of 1-2 days should be regarded as a customary visiting period. 3.3 Preparation for the visit 133