Anyone who by chance, by mistake or without express authorisation receives telegrams, images or other electronic communications signals or symbols, or listens to telephone conversations, may not record anything of this or take advantage of such in any way. Furthermore, he/she must notify the sender of having received information in error. Fullest confidentiality shall be observed in such instances. Article 48 Recording of telephone calls The party to a telephone conversation wishing to record a conversation shall, when it commences, notify the opposite party of such intent. A party need not, however, mention the recording of a conversation especially when the opposite party can clearly be assumed to be aware of the recording. Notwithstanding the first paragraph, public institutions or undertakings entrusted with such tasks by the institutions may record calls they receive when such recording is a normal part of administrative activities and necessary due to national security or public safety. The recording arrangements and notification of them to the public and employees of the institution shall comply with requirements set by the Data Protection Authority. Processing of recordings made as provided for in this Article shall comply with legislation on the protection of privacy and processing of personal data. CHAPTER X Voice telephony Article 49 Emergency calls The number 112 shall be reserved for emergency and safety services and may not be used for any other purpose. No charge may be made for calls to the emergency number 112. Article 50 Call barring An electronic communications undertaking which has been entrusted with providing universal service must, at the request of a subscriber, bar outgoing calls of defined types or calls to specific number series free of charge. Article 51 Calling line identification An electronic communications undertaking providing publicly available telephone services must offer calling line identification service in accordance with provisions of the Act on the Protection of Privacy as regards the Processing of 23/34