The content of recordings of telephone calls made through a system established to provide a telephone number to be used in an emergency, if otherwise admissible, may be proved by a copy or transcript of the recording which is authenticated by a custodian of the records of the system in a signed affidavit. The custodian must verify in the affidavit that the copy or transcript is a true and complete reproduction of the original recording and that the original recording was made at the time of the telephone call and in the course of a regularly conducted activity.
NRS 52.252