(a) Except as provided in Subdivisions (c) and (e) of this Section, no person may operate a segment of steel or plastic pipeline at a pressure that exceeds the lowest of the following:
(1) the design pressure of the weakest element in the segment, determined in accordance with this Part;
(2) the pressure obtained by dividing the pressure to which the segment was tested after construction as follows:
(i) for plastic pipe in all locations, the test pressure is divided by a factor of 1.5;
(ii) for steel pipe operated at 100 PSIG (689 kPa) gauge or more, the test pressure is divided by a factor determined in accordance with the following table:
|
Factors,1 segment - |
||
Class Location |
Installed before (Nov. 11, 1970) |
Installed on or after Nov. 12, 1970 |
Converted under ยง 255.14 |
1 |
1.1 |
1.5 |
1.5 |
2 |
1.25 |
1.5 |
1.5 |
3 |
1.5 |
1.5 |
1.5 |
4 |
1.5 |
1.5 |
1.5 |
1. For offshore pipeline segments installed, uprated or converted after July 31, 1977, that are not located on an offshore platform, the factor is 1.25. For pipeline segments installed, uprated or converted after July 31, 1977, that are located on an offshore platform or on a platform in inland navigable waters, including a pipe riser, the factor is 1.5.
(3) the highest actual operating pressure to which the segment was subjected during the five years preceding July 1, 1970, unless the segment was tested in accordance with Sections 255.505 or 255.507 of this Part during the five year period or the segment was upgraded in accordance with Sections 255.555 or 255.557 of this Part. The MAOP must not exceed the MAOP on August 30, 2011 if the MAOP is determined using this method.
(4) the pressure determined by the operator to be the maximum safe pressure after considering and accounting for records of material properties, including material properties verified in accordance with Section 255.607 of this Part, if applicable, and the history of the pipeline segment, including known corrosion and actual operating pressure.
(b) No person may operate a segment to which paragraph (a)(6) of this Section is applicable, unless overpressure protective devices are installed on the segment in a manner that will prevent the maximum allowable operating pressure from being exceeded, in accordance with Section 255.195 of this Part.
(c) Notwithstanding the other requirements of this section, an operator may operate a segment of pipeline found to be in satisfactory condition, considering its operating and maintenance history, at the highest actual operating pressure to which the segment was subjected during the five years preceding July 1, 1970, subject to the requirements of Section 255.611 of this Part.
(d) Notwithstanding the limitation of paragraph (a)(3) of this Section, an operator may maintain a previously established maximum allowable operating pressure for a cathodically protected steel or plastic pipeline provided that, when the pressure is increased above the highest pressure to which it has been subjected during the last five years, it is leakage surveyed and all leaks found are repaired in accordance with this Part.
(e) Notwithstanding the requirements in Paragraphs (a) through (d) of this Section, operators of onshore steel transmission pipelines that meet the criteria as described by Section 255.624(a) of this Part must establish and document the maximum allowable operating pressure as described by Section 255.624 of this Part.
(f) Operators of onshore steel transmission pipelines must make and retain records necessary to establish and document the MAOP of each pipeline segment in accordance with Paragraphs (a) through (e) of this Section as follows:
(1) Operators of pipelines in operation as of July 1, 2020 must retain any existing records establishing MAOP for the life of the pipeline;
(2) Operators of pipelines in operation as of July 1, 2020 that do not have records establishing MAOP and are required to reconfirm MAOP in accordance with Section 255.624 of this Part, must retain the records reconfirming MAOP for the life of the pipeline; and
(3) Operators of pipelines placed in operation after July 1, 2020 must make and retain records establishing MAOP for the life of the pipeline.