These requirements cover components of central-station burglar-alarm systems intended and specifically designated for burglary-protection use at mercantile and banking premises@ on mercantile safes@ and on bank safes and vaults. The components covered by these requirements are intended for use in a burglar-alarm system in which the operations of electrical protection circuits and devices are transmitted automatically to@ recorded in@ maintained from@ and supervised from a central-station that employs trained operators and alarm investigators who are in attendance at all times. These requirements serve as the basis of classification of central-station burglar-alarm system transmission methods. The systems may be classified as either standard line security equipment or encrypted line security equipment by virtue of the construction and performance requirements for components of that system. However@ requirements covering the complete systems are contained in the Standard for Central-Station Alarm Services@ UL 827. Protective devices installed on individual properties are further classified as to extent of protection at each location@ according to the requirements covering installation and classification (of extent) of alarm protective equipment at individual locations as published in the Standard for Installation and Classification of Burglar and Holdup Alarm Systems@ UL 681. If equipment covered by these requirements is intended for use in a combination burglar-alarm and fire-protective signaling system@ the portion of the equipment serving a fire-alarm function is covered by the Standard for Control Units for Fire-Protective Signaling Systems@ UL 864. Systems covered by these requirements operate using Class 2 remote-control and signaling circuits as defined by Article 725 of the National Electrical Code@ NFPA 70. The requirements assume that standard telephone operating practices are acceptable for leased or other lines connecting to a central-station as defined by Article 800 of the National Electrical Code@ NFPA 70. Deleted August 29@ 2001