|(a) Longitudinal or spiral welded pipe which will be subjected to service temperatures below -20 degrees Fahrenheit shall have a design pressure of less than 2/3 of the mill proof test pressure or subsequent shop or field hydrostatic test pressure, except for pipe which has been subjected to 100% radiographic or ultrasonic inspection of the longitudinal or spiral weld. (b) Circumferential butt-welds shall be fully examined by radiographic or ultrasonic inspection. Piping with an operating pressure that produces a hoop stress of less than 20% specified minimum yield stress need not be nondestructively tested provided it has been visually inspected in accordance with ANSI B31.3, 336.4.2. (c) Socket welds and fillet welds shall be fully examined by liquid penetrant. (d) Fully penetrated groove welds for branch connections required by ANSI B31.3, 327.4.4 shall be fully examined by inprocess examination in accordance with ANSI B31.3, 336.4.7, and shall also be examined by liquid penetrant after the final pass of the weld. If specified in the engineering design or specifically authorized by the inspector, examination by radiographic or ultrasonic techniques may be substituted for the examinations required by this paragraph. (e) Nondestructive examination methods, limitations on defects, qualifications of the authorized inspector, and personnel performing the examination shall meet the requirements of ANSI B31.3, 336. (f) Test records and written procedures required when conducting nondestructive examinations shall be maintained for the life of the piping system or until such time as a reexamination is conducted. (g) Records and certifications pertaining to materials, components, and heat treatment as required by ANSI B31.3, 336.5.1(c) and 336.5.3(d) shall be maintained for the life of the system.