1. Visually Inspect the Grounding Connection Point
Check the surface of the paint can for a dedicated grounding terminal or exposed metal parts.
Confirm that the location is free of paint, rust, and oil stains, and ensure the clamp can reliably contact the metal body.
If it is a plastic anti-static can, check if it is labeled "Grounding Terminal" and has a conductive path.
✅ Key Operating Points: Use a toothed anti-static clamp that can penetrate the coating for effective connection.
2. Check the Grounding Wire and Clamp Condition
Check if the grounding copper cable is broken, aged, or has loose connections.
It is recommended to use multi-strand soft copper wire with a cross-sectional area ≥6mm², of moderate length (generally not exceeding 20 meters), avoiding tangling and knots.
Check if the clamp spring is elastic and if the jaws are free of oxidation or carbon buildup.
✅ Safety Tips: Do not use ordinary iron wire or electrical wire to replace the dedicated grounding wire.
3. Connect the grounding system and confirm the bonding is complete. Securely clamp the electrostatic clamp to the grounding terminal of the paint can, and connect the other end to a dedicated grounding stake (do not connect to non-dedicated facilities such as water pipes or heating pipes).
If multiple devices are involved (such as pumps, pipelines, and receiving tanks), use bonding wires to connect all metal parts to form an equipotential body.
Follow the principle of "grounding before operation," and complete the connection before filling or pouring.
✅ Standard requirements: Bonding resistance should be <10Ω, and the total grounding resistance of the system should be ≤100Ω (≤10Ω is recommended for high-risk locations).
4. Measure the resistance value using a grounding resistance tester. Use a professional instrument (such as a ZC-8 type or clamp-on grounding resistance tester) for measurement.
Test method: Insert the current electrode (C) and potential electrode (P) of the tester into the ground, with a distance ≥20m; Connect the grounding wire to be tested to terminal E; Start the test and read the stable resistance value.
For portable 200L containers, the loop resistance can be measured directly with a clamp meter while connected.
✅ Acceptance Criteria: Grounding resistance ≤10Ω (flammable and explosive locations).
5. Post-Work Confirmation and Record Keeping: After work, allow 2–5 minutes for residual charge to dissipate naturally.
Disconnect the connections in the order of "disconnect the material pipe first, then the grounding wire."
Record the time of this test, resistance value, and operator information, and include it in the daily safety log.
✅ Management Recommendation: Establish a daily inspection sheet to achieve traceability management and comply with EHS audit requirements.
