Specification 34 73 16 Airfield Grounding.pdf

FCLP Phase 9 - Wallops Flight Facility 1696789

SECTION 34 73 16

AIRFIELD GROUNDING

11/19

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

ASTM INTERNATIONAL (ASTM)

ASTM B8 (2011; R 2017) Standard Specification for Concentric-Lay-Stranded Copper Conductors, Hard, Medium-Hard, or Soft

NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)

NFPA 407 (2022) Standard for Aircraft Fuel Servicing

UNDERWRITERS LABORATORIES (UL)

UL 467 (2013; Reprint Jun 2017) UL Standard for Safety Grounding and Bonding Equipment

1.2 SUBMITTALS

Government approval is required for submittals with a "G" or "S" classification. Submittals not having a "G" or "S" classification are for Contractor Quality Control approval. Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

As-Built Drawings; G

SD-06 Test Reports

Tests

SD-07 Certificates

Grounding Rods

Copper Conductors

Grounding Connectors

1.3 AS-BUILT DRAWINGS

Submit as-built drawngs that provide current factual information, including deviations from and amendments to the drawings and changes in the work, concealed and visible.

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PART 2 PRODUCTS

2.1 METALS

Do not use a combination of materials that forms an electrolytic couple, which accelerates corrosion in the presence of moisture, unless moisture is permanently excluded from the junction of such metals.

2.2 GROUNDING RODS

Use grounding rods, unless otherwise indicated, in accordance with UL 467 and made of copper. Use rods not less than 3/4 in in diameter and not less than 10 ft long. Submit certificates of compliance stating that the grounding rods meet the specified requirements. Provide rods with a closed eye or shepherd's hook bend having an inside diameter of not less than 1-1/2 in.

2.3 COPPER CONDUCTORS

Use copper conductors that bare number 4 AWG copper wire in accordance with ASTM B8. Submit certificates of compliance stating that the copper conductors meet the specified requirements.

2.4 GROUNDING CONNECTORS

Use grounding connectors that comply with UL 467 for the required application. Submit certificates of compliance stating that the grounding connectors meet the specified requirements.

PART 3 EXECUTION

Prior to installing grounding rods, obtain approved digging permits in accordance with Section 01 11 00 SUMMARY OF WORK.

3.1 GROUNDING POINTS

Locate the grounding points to within plus or minus 2 in of location in existing slab.

3.1.1 Pavement Recess

Set the top of the grounding rod at or not more than 1/4 in below the pavement surface grade. Provide a recess 3 in wide, and not more than 6 in long, with a smooth rounded edge in the pavement around the grounding point anchor eye to permit the entrance of lines into the eye and to allow for attachment of the grounding cable. Do not allow the depth of the recess to be deeper than the bottom of the opening of the grounding point eye.

3.1.2 Installation

3.1.2.1 New Rigid Pavement

Install the grounding rod by pushing or driving the rod through the pavement base courses and subgrade prior to concrete placement. Do not allow the installation technique chosen to damage the grounding rod. Keep hand finishing around the rod to a minimum.

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3.2 TESTS

Submit an independent testing agency's certified reports of inspections and tests, including analysis and interpretation of test results. Properly identify each report. Describe test methods and standards used. Measure resistance to ground tests as specified in NFPA 407. Submit test results to the Contracting Officer. Report immediately to the Contracting Officer ground rods that have more than 10,000 ohms of resistance.

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