3.17 Practices to Reduce Overnotifications

One Call Center

Practice Statement:

The one call center employs practices designed specifically to reduce the number of notices transmitted to facility owners/operators in which the reported excavation site is outside the owner’s/operator’s desired area of notification.

Practice Description:

The one call center employs technology that enables the facility owner/operator to determine its desired area of notification by either polygons or grids. To reduce overnotifications, technology includes, but is not limited to, the following:

  • Enables the one call center to define the proposed excavation site buffer to within approximately 800 ft
  • Enables the facility owner/operator to identify its desired area of notification to within approximately 100 ft


  • “Model One Call for the 20th and 21st Century,” AT&T (was available when the practice was created but is no longer available)
  • 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