DA Form 7452-R: Earth Ground Electrode Checklist PDF

DA Form 7452-R: Earth Ground Electrode Checklist PDF – DA Form 7452-R: Earth Ground Electrode Subsystem Checklist for New Facilities (LRA) is a key U.S. Army document used to verify proper installation and performance of grounding systems in new construction, particularly for Command, Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance (C4ISR) facilities.

This checklist ensures facilities achieve safe, effective, and reliable earth grounding, which is critical for electrical safety, lightning protection, equipment protection, and operational reliability.

What Is DA Form 7452-R?

DA Form 7452-R (February 2002) is titled “Earth Ground Electrode Subsystem Checklist for New Facilities (LRA)”. It serves as a standardized inspection tool referenced in TM 5-690, Grounding and Bonding in Command, Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance (C4ISR) Facilities.

Note: It is sometimes referred to as DD Form 7452-R in civilian contexts, but it is a Department of the Army (DA) form.

The form helps inspectors, engineers, and contractors document and verify that the earth electrode subsystem meets design specifications, providing a low-resistance path to ground for fault currents, lightning strikes, and static electricity.

Download the official form here: DA Form 7452-R PDF

Why Proper Earth Grounding Matters in U.S. Facilities?

A well-designed earth ground electrode subsystem:

  • Protects personnel and equipment from electrical faults.
  • Mitigates damage from lightning and power surges.
  • Ensures signal integrity in sensitive electronic systems.
  • Helps comply with safety standards (e.g., NFPA 70/NEC principles adapted for military facilities) and Army technical manuals.

In new facility construction or major renovations, the earth electrode subsystem typically includes ground rods, interconnecting conductors (often forming a ring around the building), ground wells, and risers. The goal is low resistance to earth, often targeting values well below standard commercial requirements for mission-critical C4ISR sites.

Key Components Checked on DA Form 7452-R

The checklist systematically verifies multiple elements:

  1. Facility and Site Information — Facility name, location, date, inspector, and soil resistivity (ohm-cm, obtained from site survey).
  2. Resistance Measurements — Resistance of the completed earth electrode subsystem (ohms).
  3. Sketch of the Subsystem — Dimensions, locations of electrodes, conductors, other buried metals, lightning/power/signal risers, and ground wells (or attach corrected drawings).
  4. Ground Rods — Type, size, number of additional rods, positioning/installation, and physical condition.
  5. Ground Conductors — Type, size, material, spacing, and buried depth.
  6. Interconnecting Conductors — Type, size, material.
  7. Connectors/Fittings — Proper type, size, material, and resistance between connection points.
  8. Risers — Installation, sizing, and location.
  9. Future Inaccessible Joints/Connections — Proper installation and connection.
  10. Ground Wells — Installation as specified and measured resistance-to-earth.

Each item includes YES/NO checkboxes for compliance, ensuring thorough quality control during construction acceptance.

How to Use DA Form 7452-R? (Step-by-Step Guidance)

  • Preparation: Conduct soil resistivity testing before or during installation.
  • Inspection Timing: Perform during and after installation of the earth electrode subsystem, before backfilling inaccessible components.
  • Testing: Use approved methods (e.g., fall-of-potential) to measure overall resistance and individual connections.
  • Documentation: Fill out all fields, attach sketches/drawings and test data. Retain records for facility acceptance and future maintenance.
  • Reference Standard: Always follow TM 5-690 for detailed procedures, design criteria, and acceptance limits.

Pro Tip for Contractors and Army Personnel: Complete this form as part of the broader grounding inspection program in TM 5-690, which includes separate checklists for fault protection, lightning protection, and signal reference subsystems.

  • DA Form 7452-4-R — Earth Electrode Subsystem Checklist for Existing Facilities.
  • Other companion forms in the 7452 series cover fault protection, lightning, signal grounds, etc.
  • Primary guidance: TM 5-690 (available via Army Publications sites).

Best Practices for Earth Ground Electrode Systems

  • Use copper-clad steel rods (typically 3/4″ x 10′ or longer) driven to depth.
  • Install a perimeter ring conductor with rods at intervals (e.g., every 15-20 feet or per design).
  • Bond all nearby metallic objects (pipes, rebar, tanks) to the system.
  • Ensure exothermic welding or approved mechanical connectors for buried joints.
  • Locate electrodes to minimize resistance (avoid dry/rocky areas when possible; use ground wells or enhancements in poor soil).

For U.S.-based military construction projects, integrating DA Form 7452-R early helps avoid costly rework and ensures compliance with Army Corps of Engineers (COE) standards.

Need the form or more details? Download it directly from the official Army source linked above. For full technical guidance, consult the latest version of TM 5-690 or your local Corps of Engineers representative.