Sec. 36.124  Tandem switching equipment--Category 2.

    (a) Tandem switching equipment is contained in Accounts 2210, 2211, 
2212 and 2215. It includes all switching equipment in a tandem central 
office, including any associated tandem switchboard positions and any 
intertoll switching equipment. Intertoll switching equipment includes 
switching equipment used for the interconnection of message toll 
telephone circuits with each other or with local or tandem telephone 
central office trucks, intertoll dial selector equipment, or intertoll 
trunk equipment in No. 5 type electronic offices. Equipment, including 
switchboards used for recording of calling telephone numbers and other 
billing information in connection with customer dialed charge traffic is 
included with Local Switching Equipment--Category 3.
    (1) At toll center toll offices, intertoll switching equipment 
comprises equipment in the toll office used in the interconnection of: 
Toll center to toll center circuits; toll center to tributary circuits; 
tributary to tributary circuits; toll center to tandem circuits or in 
the interconnection of the aforementioned types of circuits with trunks 
to local offices in the toll center city, i.e., interconnection with 
toll switching trunks, operator trunks, information trunks, testing 
trunks, etc. Equipment associated with the local office end of such 
trunks is included with local switching equipment or switchboard 
categories as appropriate.
    (2) At tributary offices, this category includes intertoll switching 
equipment similar to that at toll center toll offices if it is used in 
the interconnection of: Tributary to tributary circuits; tributary to 
subtributary circuits; subtributary to subtributary circuits; toll 
center to subtributary circuits; or if it is used jointly in the 
interconnection of any of the aforementioned types of circuits and in 
the interconnection of such toll circuits with trunk circuits for the 
handling of traffic terminating in the tributary office. Where 
comparable equipment has no joint use but is used only for the handling 
of traffic terminating in the tributary office, it is included in the 
local switching equipment category.
    (3) At all switching entities, this category includes intertoll 
switching equipment similar to that at toll center toll offices if it is 
used in the interconnection of switched private line trunks or TWX 
switching plant trunks when these functions are in addition to the 
message telephone switching function. Switching entities wholly 
dedicated to switching of special services are assigned to Category 3--
Local Switching Equipment.
    (b) The costs of central office equipment items assigned this 
category are to be directly assigned when possible. When direct 
assignment is not possible the costs shall be apportioned among the 
operations on the basis of the relative number of study area minutes of 
use of this equipment.