Barrel: 42 U.S. gallons.

Batch: A quantity of petroleum product of like specifications moved through the pipeline as an identifiable unit.

Booster Station: A pump station used to increase the pressure of oil received through a main pipeline to transmit it to the next station or terminal.

Cold Zone: Area safe for necessary personnel.

Common Carrier: Any transportation system available for use by the public for transporting cargo; almost all interstate pipelines are common carriers.

Crude Oil: The basic raw mineral pumped from the earth. There are many different grades of crude, each containing various vapors, liquids and solids. This crude is changed at a refinery into products.

Gathering Lines: A small diameter pipeline used in gathering crude oil from the oil field to a common point for further movement to a trunk line.

Interface: The mixture which occurs in normal pipeline operations between batches of petroleum products or crude having different specifications. Also called "slop" or "transmix."

High Pressure Pipelines: Pipe systems which operate at 600 psi to 2000 psi and higher.

Hot Zone: Area where hazardous vapors and liquids are present.

Line Section: A continuous run of pipe between locations.

Manifold: An arrangement of piping valves to provide interconnecting links between a number of pumps, tanks, and lines at a pump station.

Pig: A device placed inside a pipeline that is used to clean or scrape residues from the inner wall of the pipe.

Pipeline System: All parts of the physical facilities through which commodities move, including line pipe, valves, pumping units, metering stations and tankage.

Products: Refined substances made from crude oil. Gasoline, fuel oil, butane and a host of various other petroleum products that we transport in pipelines.

Smart Pig: A device placed inside the pipeline to provide data about the pipeline, such as measuring dents or locating corrosion.

Tank Farm: A group of tanks connected to a pipeline through which oil is moved.

Trunk Line: A main pipeline.