3.2 Specifically Defined Geopolitical Service Area with No Overlap

One Call Center

Practice Statement:

The one call centers serving a specifically defined geopolitical area are structured so that an excavator need only make one call, and a facility owner/operator need only belong to a single one call center.

Practice Description:

One call programs are designed to promote ease of use for members (facility owners/operators) and excavators. Although this ease of use is enhanced when a one call center serves a specifically defined geopolitical area that does not overlap with the service area of another one call center, non-overlapping service areas are not essential. There are three requirements that a one call program must meet to be considered as having implemented this best practice:

  • The program permits an excavator to use a single point of contact to submit and follow up on a notice of intent to excavate and to notify affected facility owners/operators.
  • The program permits a facility owner/operator to join a single one call center and receive all appropriate notices.
  • The program is designed so that all pertinent information is shared among one call centers in the event more than one exists.


  • One Call Systems International Voluntary Recognition Program
  • Existing operating practices from various states’ one call centers
  • NTSB Safety Study (NTSB/SS-97/01; PB97-917003)


One Call Center One Call Center

Facility Owner Facility Owner

Excavator Excavator

Locator Locator

Project Owner Project Owner

Designer Designer