NLSI - Providing expert training and consulting for lightning problems

Contact Us »
Site Map »
Home »
Back to Section 5 Contents »

 ~ National Lightning Safety Institute ~

Section 5.1.10

Lightning Safety Decision Tree for Facilities

By Richard Kithil, President & CEO, NLSI

1. Determine if lightning protection is beneficial:
- Risk Analysis and Probability Study
- Cost vs. Benefit?
- See IEC 1662, Assessment of Risk

2. If facility already has been insulted by lightning:
- Omit Step #1
- Examine damaged components
- Determine vulnerabilities

3. Determine if lightning protection is required--See guidance contained in IEC 62305, IEEE 142, IEEE 1100, FAA 019d, FAA 6950, MIL 419A, NASA E0012E, NAVSEA OP5, AFI 32-1065, AFM 385-64, DOE M440.1-1, BS 6651, etc.

4. Examine facility and specify sub-category protection requirements in accordance with:

4.1 Air Terminal Options: Franklin Rod, Overhead, Mast, or Quasi-Faraday Cage designs

4.2 Bonding: Achieve equi-potential of all adjacent metallics

4.3 Shielding: Employ where beneficial

4.4 Surge Suppression: Protect all AC power, data, I/Os, etc.

4.5 Grounding: Achieve volumetric efficiencies

4.6 Lightning Detector: For start/stop of auxiliary AC power

4.7 Testing: Verify low impedance paths

4.8 Maintenance: Periodic inspections, record-keeping

5. Develop procedures and policy for stop/start of activities during lightning threat conditions.


About NLSI | NLSI Business Services | Lightning Incidents
Personal Lightning Safety | Structural Lightning Safety | Reference Information


National Lightning Safety Institute
Providing expert training and consulting for lightning problems