What term is used for individuals who patrol pipelines on foot or vehicle?

The term "linewalkers" specifically refers to individuals who are tasked with patrolling pipelines, either on foot or by vehicle. This role involves thoroughly inspecting pipelines for signs of leaks, damage, or other potential issues that could affect safety and operations. Linewalkers are trained to recognize various indicators of pipeline integrity and to take appropriate measures based on their findings.

While other terms like "patrol officers," "inspectors," and "field agents" may relate to roles that involve monitoring or overseeing operations, they do not specifically encapsulate the act of walking along or driving adjacent to pipeline corridors, which is a fundamental aspect of what linewalkers do. Therefore, "linewalkers" is the most accurate designation for this particular job function within the pipeline industry.