API RP 1166:2005

Provides a consistently applied decision making process for monitoring and observing of excavation and other activities on or near pipeline Rights-of -Way for "hazardous liquid" and "natural and other gas" transmission pipelines. ( Note: One call provisions and laws vary by state and it is the operator's responsibility to be familiar with and comply with all applicable one-call laws). This document's purpose is to protect the public, excavation employees, and the environment by preventing damage to pipeline assets from excavation activities.