Managing System Integrity for Hazardous Liquid Pipelines 
API Standard 1160
First Edition, November 2001

“...10 Mitigation Options

10.3 DETECTING AND MINIMIZING UNINTENDED PIPELINE RELEASES

In the event of an unintended release from within a pipeline system, the consequences can be minimized by:

—Reducing the time required for detection of the release.
—Reducing the time required to locate the release.
—Reducing the volume that can be released.
—Reducing the emergency response time.

10.3.2 Types of Release Detection Systems

Release detection cable. Release detection sensing cables are designed to alarm after contact with liquid hydrocarbons at any point along their length. The presence of hydrocarbons creates a circuit between two sensing wires and triggers an alarm. Typically, leak detection cable is installed in slotted PVC conduitthat is buried in the pipe trench along or below the pipeline. These systems provide continuous monitoring via electronic control units capable of interfacing with SCADA technology and are able to provide leak location information...”