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<br />An unspliced grounding electrode conductor shall be permitted to be run to any convenient grounding electrode <br />available in the grounding electrode system or to one or more grounding electrode(s) individually. It shall be <br />sized for the largest grounding electrode conductor required among all the'electrodes connected to it. <br />jlc-.-ta,,1 <br /> <br />The grounding electrode conductor shall be unspliced or spliced by means of irreversible compression-type <br />connectors listed for the purpose or by the exothermic welding process. <br /> <br />Interior metal water piping located more than 5 ft (1.52 m) from the point of entrance to the building shall not <br />be used as a part of the grounding electrode system or as a conductor to interconnect electrodes that are part of <br />the grounding electrode system. <br /> <br />Exception: In industrial and commercial buildings where conditions of maintenance and supervision ensure <br />that only qualified persons will service the installation and the entire length of the interior metal water pipe that <br />is being used for the conductor is exposed. I. e_ta',i <br /> <br />FPN: See Sections 547-8 and 547-9 for special grounding and bonding requirements for agricultural buildings. <br /> <br />(a) Metal Underground Water Pipe. A metal underground water pipe in direct contact with the earth for 10 ft <br />(3.05 m) or more (including any metal well casing effectively bonded to the pipe) and electrically continuous <br />(or made electrically continuous by bonding around insulating joints or sections or insulating pipe) to the points <br />of connection of the grounding electrode conductor and the bonding conductors. .e_ta'V~ <br /> <br />(1) Continuity. Continuity of the grounding path or the bonding connection to interior piping shall not rely on <br />water meters or filtering devices and similar equipment. <br /> <br />(2) Supplemental Electrode Required. A metal underground water pipe shall be supplemented by an <br />additional electrode of a type specified in Sections 250-50 or 250-52. Where the supplemental electrode is a <br />made electrode of the rod, pipe, or plate type, it shall comply with Section 250-56. The supplemental electrode <br />shall be permitted to be bonded to the grounding electrode conductor, the grounded service-entrance conductor, <br />the nonflexible grounded service raceway, or any grounded service enclosure. !Ie_ta,,' <br /> <br />Exception: The supplemental electrode shall be permitted to be bonded to the interior metal water piping at <br />any convenient point as covered in Section 250-50, Exception. <br /> <br />Where the supplemental electrode is a made electrode as in Section 250-52(c) or (d), that portion of the bonding <br />jumper that is the sole connection to the supplemental grounding electrode shall not be required to be larger than <br />No.6 copper wire or No. 4 aluminum wire. .je___a,gl <br /> <br />(b ) Metal Frame of the Building or Structure. The metal frame of the building or structure, where effectively <br />grounded. <br /> <br />(c) Concrete-Encased Electrode. An electrode encased by at least 2 in. (50.8 mm) of concrete, located within <br />and near the bottom of a concrete foundation or footing that is in direct contact with the earth, consisting of at <br />least 20 ft: (6.1 m) of one or more bare or zinc galvanized or other electrically conductive coated steel <br />reinforcing bars or rods of not less than ~-in. (12.7-mm) diameter, or consisting of at least 20 ft (6.1 m) of bare <br />copper conductor not smaller than No.4. Reinforcing bars shall be permitted to be bonded together by the usual <br />steel tie wires or other effective means. ile~,~ <br /> <br />(d) Ground Ring. A ground ring encircling the building or structure, in direct contact with the earth at a depth <br />