Which class of the system applies when the premise only has a single equipment room (ER), and it is the only telecommunications space administered?

TIA-606-B defines Class 1 as the administration level for a single telecommunications space, such as one equipment room (ER) or telecommunications room (TR), within a small or single-tenant facility. Because no backbone cabling connects multiple spaces, the records, labeling, and documentation requirements are scoped to that one room only.

Class 2 applies to facilities with multiple telecommunications spaces within a single building, requiring backbone administration between those spaces.

Class 3 is used for campus environments spanning multiple buildings, requiring administration of interbuilding backbone infrastructure.

Class 4 covers multi-campus or geographically dispersed enterprise sites, representing the most complex administration level.