⚡ Diesel Storage Tanks grounding & lightning protection
mandatory grounding · lightning based on thickness · ring grounding · floating roof bonding
Mandatory Grounding for All Metal Tanks
- Absolute safety requirement – national standards mandate a reliable grounding system for all metal diesel storage tanks to prevent lightning strikes and static electricity accumulation.
- Above‑ground and buried – both types require a solid electrical connection to the earth for safely dissipating charges and protecting against fires or explosions.
Lightning Protection Based on Tank Thickness
- Thick steel roof (≥4 mm) – the tank itself can act as a lightning rod, requiring no additional rods.
- Thinner roof (<4 mm) – independent lightning rods or wires must be installed to cover the entire tank.
- Regardless of thickness – a robust grounding system remains mandatory.
Ring Grounding & Resistance Standards
- Ring‑shaped grounding system – grounding points must be installed at no fewer than two locations, evenly distributed around the tank's perimeter.
- Resistance limit – ideally ≤10 ohms to ensure rapid and safe channelling of massive lightning currents into the earth.
Special Grounding for Floating Roof Tanks
- Electrical bonding – the floating roof must be bonded to the main tank body using heavy‑duty conductive cables.
- Continuous connection – essential for draining static electricity generated by moving roof friction and preventing lightning‑induced sparks in the vapour space.
● always comply with NFPA 780 and IEC 62305 standards ● regular testing of grounding resistance is mandatory ●