# 3172.5 Definitions.
As used in this subpart, the term:
*2M, 3M, 5M, 10M,* and *15M* mean the pressure ratings used for equipment with a working pressure rating of the equivalent thousand pounds per square inch (psi) (2M=2,000 psi, 3M=3,000 psi, etc.).
*Abnormal pressure zone* means a zone that has either pressure above or below the normal gradient for an area and/or depth.
*Bleed line* means the vent line that bypasses the chokes in the choke manifold system; also referred to as panic line.
*Blooie line* means a discharge line used in conjunction with a rotating head.
*Drilling spool* means a connection component with both ends either flanged or hubbed, with an internal diameter at least equal to the bore of the casing, and with smaller side outlets for connecting auxiliary lines.
*Exploratory well* means any well drilled beyond the known producing limits of a pool.
*Fill-up line* means the line used to fill the hole when the drill pipe is being removed from the well. It is usually connected to a 2-inch collar that is welded into a drilling nipple.
*Flare line* means a line used to carry gas away from the rig to be burned at a safer location. The gas comes from the degasser, gas buster, separator, or when drill stem testing, directly from the drill pipe.
*Functionally operated* means activating equipment without subjecting it to well-bore pressure.
*Isolating* means using cement to protect, separate, or segregate usable water and mineral resources.
*Lease* means any contract, profit-share agreement, joint venture, or other agreement issued or approved by the United States under a mineral leasing law that authorizes exploration for, extraction of, or removal of oil or gas (see 43 CFR 3160.0-5).
*Lessee* means a person holding record title in a lease issued by the United States (see 43 CFR 3160.0-5).
*Make-up water* means water that is used in mixing slurry for cement jobs and plugging operations and is compatible with the cement constituents being used.
*Manual locking device* means any manually activated device, such as a hand wheel, etc., that is used for the purpose of locking the preventer in the closed position.
*Mud for plugging purposes* means a slurry of bentonite or similar flocculent/viscosifier, water, and additives needed to achieve the desired weight and consistency to stabilize the hole.
*Mudding up* means adding materials and chemicals to water to control the viscosity, weight, and filtrate loss of the circulating system.
*Operating rights owner (or owner)* means a person or entity holding operating rights in a lease issued by the United States. A lessee also may be an operating rights owner if the operating rights in a lease or portion thereof have not been severed from record title.
*Operational* means capable of functioning as designed and installed without undue force or further modification.
*Operator* means any person or entity, including but not limited to the lessee or operating rights owner, who has stated in writing to the authorized officer his/her responsibility for the operations conducted in the leased lands or a portion thereof.
*Precharge pressure* means the nitrogen pressure remaining in the accumulator after all the hydraulic fluid has been expelled from beneath the movable barrier.
*Prompt correction* means immediate correction of violations, with drilling suspended if required in the discretion of the authorized officer.
*Prospectively valuable deposit of minerals* means any deposit of minerals that the authorized officer determines to have characteristics of quantity and quality that warrant its protection.
*Tagging the plug* means running in the hole with a string of tubing or drill pipe and placing sufficient weight on the plug to ensure its integrity. Other methods of tagging the plug may be approved by the authorized officer.
*Targeted tee or turn* means a fitting used in pressure piping in which a bull plug or blind flange of the same pressure rating as the rest of the approved system is installed at the end of a tee or cross, opposite the fluid entry arm, to change the direction of flow and to reduce erosion.
*Usable water* means generally those waters containing up to 10,000 parts per million (ppm) of total dissolved solids.
*Weep hole* means a small hole that allows pressure to bleed off through the metal plate used in covering well bores after abandonment operations.