ESN

1. Emergency Service Number A three-digit number that is assigned to the caller's telephone number in the tandem office translations. The emergency...

Understanding Emergency Service Zones: Key Public Safety Terms Explained

Emergency Service Zone. An area in which all 9‐1‐1 calls are routed to a specific PSAP and in which all residents are served by the same responding...

ESG

Emergency Services Gateway.

ESCO

Emergency Service Central Office Number. The information delivered to the PSAP when there is an ANI failure between the end office and the 9‐1‐1...