255.557 Upgrading to a pressure less than 125 psig (862 kPa).

(a)Unless the requirements of this section have been met, no person may subject a segment of steel or plastic pipeline to a higher maximum allowable operating pressure that is less than 125 psig (862 kPa).#

(b)Increasing the maximum allowable operating pressure for cast iron, ductile iron, and wrought iron pipeline segments is prohibited without prior approval.#

(c)Before increasing the operating pressure above the previously established maximum allowable operating pressure, the operator shall comply with the following requirements:#

(1)review the design, operating and maintenance history of the segment of pipeline;#

(2)make a leakage survey (if it has been more than one year since the last survey) and repair any leaks that are found;#

(3)make any repairs, replacements or alterations in the segment of pipeline that are necessary for safe operation at the increased pressure;#

(4)for effectively coated steel systems, establish adequate cathodic protection in compliance with section 255.463 of this Part;#

(5)for ineffectively coated or bare steel systems, perform a review for active corrosion, isolate and cathodically protect all coated segments and all services, and where active corrosion exists establish adequate cathodic protection in compliance with section 255.463 of this Part;#

(6)reinforce or anchor offsets, bends and dead ends in pipe joined by compression couplings or bell and spigot joints to prevent failure of the pipe joint, if the offset, bend, or dead end is exposed in an excavation;#

(7)isolate the segment of pipeline in which the pressure is to be increased from any adjacent segment that will continue to be operated at a lower pressure; and#

(8)if the pressure in mains or service lines, or both, is to be higher than the pressure delivered to the customer, install a service regulator of adequate capacity on each service line and test each new or existing service regulator to verify that it is functioning properly and adequately vented in compliance with sections 255.355(b) and 255.744(e) of this Part. Pressure may be increased as necessary to test each regulator, after a regulator has been installed on each pipeline subject to the increased pressure.#

(d)After complying with subdivision (c) of this section, the increase in maximum allowable operating pressure must be made in increments that are equal to 10 psig (69 kPa) or 25 percent of the total pressure increase, whichever produces the fewer number of increments. Whenever the requirements of paragraph (c)(8) of this section apply, there must be at least two approximately equal incremental increases.#