What Definitions Apply to this Chapter? [49 CFR 192.903]

(A)A. The following definitions apply to this Chapter.#

Assessment―the use of testing techniques as allowed in this Chapter to ascertain the condition of a covered pipeline segment.#

Confirmatory Direct Assessment―an integrity assessment method using more focused application of the principles and techniques of direct assessment to identify internal and external corrosion in a covered transmission pipeline segment.#

Covered Segment or Covered Pipeline Segment―a segment of gas transmission pipeline located in a high consequence area. The terms gas and transmission line are defined in §503.#

Direct Assessment―an integrity assessment method that utilizes a process to evaluate certain threats (i.e., external corrosion, internal corrosion and stress corrosion cracking) to a covered pipeline segment's integrity. The process includes the gathering and integration of risk factor data, indirect examination or analysis to identify areas of suspected corrosion, direct examination of the pipeline in these areas, and post assessment evaluation.#

High Consequence Area―an area established by one of the methods described in Subparagraphs a or b as follows:#

(a)a. An area defined as:#

(i)i. a Class 3 location under §505; or#

(ii)ii. a Class 4 location under §505; or#

(iii)iii. any area in a Class 1 or Class 2 location where the potential impact radius is greater than 660 feet (200 meters), and the area within a potential impact circle contains 20 or more buildings intended for human occupancy; or#

(iv)iv. any area in a Class 1 or Class 2 location where the potential impact circle contains an identified site.#

(b)b. The area within a potential impact circle containing:#

(i)i. 20 or more buildings intended for human occupancy, unless the exception in Subparagraph d applies; or#

(ii)ii. an identified site.#

(c)c. Where a potential impact circle is calculated under either method a. or b. to establish a high consequence area, the length of the high consequence area extends axially along the length of the pipeline from the outermost edge of the first potential impact circle that contains either an identified site or 20 or more buildings intended for human occupancy to the outermost edge of the last contiguous potential impact circle that contains either an identified site or 20 or more buildings intended for human occupancy (see Figure E.I.A. in §5109 Appendix E).#

(d)d. If in identifying a high consequence area under Clause a.iii of this definition or Clause b.i of this definition, the radius of the potential impact circle is greater than 660 feet (200 meters), the operator may identify a high consequence area based on a prorated number of buildings intended for human occupancy within a distance 660 feet (200 meters) from the centerline of the pipeline until December 17, 2006. If an operator chooses this approach, the operator must prorate the number of buildings intended for human occupancy based on the ratio of an area with a radius of 660 feet (200 meters) to the area of the potential impact circle (i.e., the prorated number of buildings intended for human occupancy is equal to 20 x (660 feet) [or 200 meters] / potential impact radius in feet [or meters] 2).#

Identified Site―each of the following areas:#

(a)a. an outside area or open structure that is occupied by 20 or more persons on at least 50 days in any 12 month period. (The days need not be consecutive.) Examples include but are not limited to, beaches, playgrounds, recreational facilities, camping grounds, outdoor theaters, stadiums, recreational areas near a body of water, or areas outside a rural building such as a religious facility); or#

(b)b. a building that is occupied by 20 or more persons on at least five days a week for 10 weeks in any 12 month period. (The days and weeks need not be consecutive). Examples include, but are not limited to, religious facilities, office buildings, community centers, general stores, 4-H facilities, or roller skating rinks); or#

(c)c. a facility occupied by persons who are confined, are of impaired mobility, or would be difficult to evacuate. Examples include but are not limited to hospitals, prisons, schools, day-care facilities, retirement facilities or assisted-living facilities.#

Potential Impact Circle―a circle of radius equal to the potential impact radius (PIR).#

Potential Impact Radius (PIR)—the radius of a circle within which the potential failure of a pipeline could have significant impact on people or property. PIR is determined by the formula r = 0.69 * [square root of (p*d2)] , where 'r' is the radius of a circular area in feet surrounding the point of failure, 'p' is the maximum allowable operating pressure (MAOP) in the pipeline segment in pounds per square inch and 'd' is the nominal diameter of the pipeline in inches.#

NOTE: 0.69 is the factor for natural gas. This number will vary for other gases depending upon their heat of combustion. An operator transporting gas other than natural gas must use Section 3.2 of ASME B31.8S incorporated by reference, see §507) to calculate the impact radius formula#

Remediation―a repair or mitigation activity an operator takes on a covered segment to limit or reduce the probability of an undesired event occurring or the expected consequences from the event.#

AUTHORITY NOTE: Promulgated in accordance with R.S. 30:501 et seq.#

HISTORICAL NOTE: Promulgated by the Department of Natural Resources, Office of Conservation, Pipeline Division, LR 30:1273 (June 2004), amended LR 31:685 (March 2005), LR 33:483 (March 2007), LR 35:2811 (December 2009), LR 44:1042 (June 2018), amended by the Department of Conservation and Energy, Office of Enforcement, LR 51:1835 (November 2025).#