| S.No. | Checkpoint | IS Requirement | Status |
|---|---|---|---|
| A. AIR TERMINALS & STRIKE TERMINALS | |||
| A1 | Air terminals (lightning rods) are installed at all high points: roof peaks, antenna masts, chimney tops Acceptance: Air terminals at all peaks/protrusions extending ≥ 0.5 m above roof, spacing ≥ 1.5 m for Class I buildings | Cl. 3.1.1 — Air terminal placement | OK NC NA HOLD |
| A2 | Air terminals are copper or aluminum rods, minimum 16 mm diameter, rigidly mounted with secure brackets Acceptance: Copper Ø ≥ 16 mm or Aluminum Ø ≥ 25 mm, mounted vertical or inclined ≤ 45°, brackets tight and corrosion-free | Cl. 3.2.1 — Air terminal material | OK NC NA HOLD |
| A3 | Air terminal height extends minimum 1.5-2.0 m above roof level to create protective cone; coverage verified by design Acceptance: Terminal height ≥ 1.5 m for Class I, ≥ 2.0 m for Class II, protective cone verified against design drawings | Cl. 3.2.2 — Terminal height | OK NC NA HOLD |
| A4 | Air terminal to down conductor connections are bolted or welded; no soldered connections used Acceptance: M10 bolt minimum or welded connection, no solder, connection resistance ≤ 0.01 Ω | Cl. 3.3.1 — Terminal connection | OK NC NA HOLD |
| A5 | All metallic roof structures (if present) are bonded to lightning protection system at multiple points Acceptance: Metal sheets/gutters bonded at min. 2 points per structure, connection resistance ≤ 0.1 Ω | Cl. 3.4.1 — Metal roof bonding | OK NC NA HOLD |
| B. DOWN CONDUCTORS | |||
| B1 | Down conductors are copper (minimum 10 mm²) or aluminum (minimum 16 mm²); installed vertically along building exterior Acceptance: Copper ≥ 10 mm² or Aluminum ≥ 16 mm², routed vertically or at steep angle, min. spacing 10 m apart | Cl. 4.1.1 — Down conductor size | OK NC NA HOLD |
| B2 | Down conductors are securely attached to building at intervals ≤ 1.0 m with proper clips/clamps (non-corroding) Acceptance: Support clips every ≤ 1.0 m, clips non-corroding (stainless steel or nylon), no sagging or movement | Cl. 4.2.1 — Down conductor support | OK NC NA HOLD |
| B3 | Down conductors are routed away from active electrical installations; minimum separation 2.0 m where not bonded Acceptance: Separation ≥ 2.0 m from power cables/DB or bonded together at multiple points if crossing required | Cl. 4.3.1 — Electrical separation | OK NC NA HOLD |
| B4 | Down conductors are not routed through interior walls if possible; if interior routing necessary, conduit protection is provided Acceptance: Exterior routing preferred; interior routing in fire-rated conduit, clearance from flammable materials maintained | Cl. 4.4.1 — Interior routing protection | OK NC NA HOLD |
| B5 | Down conductor connections at junctions are bolted (M10 minimum) or welded; connections tight and corrosion-free Acceptance: M10 bolts minimum or welded, connection resistance ≤ 0.01 Ω, no loose fittings or corrosion | Cl. 4.5.1 — Down conductor joints | OK NC NA HOLD |
| B6 | Down conductors are continuous from roof terminal to earth electrode; no breaks or interruptions in path Acceptance: Continuity verified with multi-meter: resistance ≤ 0.1 Ω per 10 m section, full path tested end-to-end | Cl. 4.6.1 — Conductor continuity | OK NC NA HOLD |
| B7 | Down conductors are clearly visible or marked for identification; color-coded or labeled per building section Acceptance: Color-coded (e.g., yellow/green stripe) or labeled with section ID, legible markings at 5 m intervals | Cl. 4.7.1 — Conductor identification | OK NC NA HOLD |
| C. EARTH TERMINATION | |||
| C1 | Lightning protection earth electrodes are separate from building main earth or bonded together (if combined system used) Acceptance: Separate pits ≥ 10 m apart OR single bonded system with coordination, design documented | Cl. 5.1.1 — Earth system design | OK NC NA HOLD |
| C2 | Lightning earth electrode pit is designed per IS 3043 guidelines: minimum 1.0 m × 1.0 m × 2.5 m deep Acceptance: Pit dimensions ≥ 1.0 × 1.0 × 2.5 m, charcoal-salt backfill, electrode min. Ø 16 mm copper, all per IS 3043 | Cl. 5.2.1 — Earth pit design | OK NC NA HOLD |
| C3 | Multiple earth electrodes (minimum 2) are installed if lightning class requires low resistance (target ≤ 10 Ω) Acceptance: Class I: ≤ 10 Ω; Class II: ≤ 10 Ω; electrodes spaced ≥ 2 m apart, bonded in parallel | Cl. 5.3.1 — Multi-electrode configuration | OK NC NA HOLD |
| C4 | Earth conductor from down conductors to earth pit is copper ≥ 10 mm² or aluminum ≥ 16 mm², routed safely Acceptance: Copper ≥ 10 mm² or Aluminum ≥ 16 mm², routed via conduit if exposed, joints bolted/welded | Cl. 5.4.1 — Earth lead sizing | OK NC NA HOLD |
| C5 | Lightning earth resistance is measured and recorded; value ≤ 10 Ω for Class I, ≤ 10 Ω for Class II buildings Acceptance: Measured resistance ≤ 10 Ω, test method documented (3-point or fall-of-potential), results recorded | Cl. 5.5.1 — Earth resistance testing | OK NC NA HOLD |