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OC Motor Pool and Maintenance Shop <br />PDC Project 23017 Grounding and Bonding for Electrical <br />Systems 26 05 26 - 2 <br />PART 2 PRODUCTS <br />2.01 GROUNDING AND BONDING REQUIREMENTS <br />A.Existing Work: Where existing grounding and bonding system components are indicated to be <br />reused,they may be reused only where they are free from corrosion,integrity and continuity are <br />verified,and where acceptable to the authority having jurisdiction. <br />B.Do not use products for applications other than as permitted by NFPA 70 and product listing. <br />C.Unless specifically indicated to be excluded,provide all required components,conductors, <br />connectors,conduit,boxes,fittings,supports,accessories,etc.as necessary for a complete <br />grounding and bonding system. <br />D.Where conductor size is not indicated,size to comply with NFPA 70 but not less than applicable <br />minimum size requirements specified. <br />E.Grounding System Resistance: <br />1.Achieve specified grounding system resistance under normally dry conditions unless <br />otherwise approved by Architect.Precipitation within the previous 48 hours does not <br />constitute normally dry conditions. <br />2.Grounding Electrode System: Not greater than 5 ohms to ground,when tested according to <br />IEEE 81 using "fall-of-potential"method. <br />3.Between Grounding Electrode System and Major Electrical Equipment Frames,System <br />Neutral,and Derived Neutral Points: Not greater than 0.5 ohms,when tested using "point-to- <br />point"methods. <br />F.Grounding Electrode System: <br />1.Provide connection to required and supplemental grounding electrodes indicated to form <br />grounding electrode system. <br />a.Provide continuous grounding electrode conductors without splice or joint. <br />b.Install grounding electrode conductors in raceway where exposed to physical damage. <br />Bond grounding electrode conductor to metallic raceways at each end with bonding <br />jumper. <br />2.Metal Underground Water Pipe(s): <br />a.Provide connection to underground metal domestic and fire protection (where present) <br />water service pipe(s)that are in direct contact with earth for at least 10 feet at an <br />accessible location not more than 5 feet from the point of entrance to the building. <br />b.Provide bonding jumper(s)around insulating joints/pipes as required to make pipe <br />electrically continuous. <br />c.Provide bonding jumper around water meter of sufficient length to permit removal of <br />meter without disconnecting jumper. <br />3.Metal In-Ground Support Structure: <br />a.Provide connection to metal in-ground support structure that is in direct contact with <br />earth in accordance with NFPA 70. <br />4.Concrete-Encased Electrode: <br />a.Where metallic structural components meet the definition of a concrete encased <br />electrode as defined in NEC 250.52,the concrete encased electrode shall be bonded to <br />the grounding electrode system per NEC 250.50.Coordinate with the structure prior to <br />pouring concrete foundations. <br />b.Provide connection to concrete-encased electrode consisting of not less than 20 feet of <br />either steel reinforcing bars or bare copper conductor not smaller than 4 AWG <br />embedded within concrete foundation or footing that is in direct contact with earth in <br />accordance with NFPA 70. <br />5.Ground Rod Electrode(s): <br />a.Space electrodes not less than 10 feet from each other and any other ground electrode <br />until maximum allowed resistance to ground is achieved. <br />b.Where location is not indicated,locate electrode(s)at least 5 feet outside building <br />perimeter foundation as near as possible to electrical service entrance;where possible, <br />Docusign Envelope ID: EF9C08D2-5B75-438B-8D6D-8473F81BD7C4