ACCESS TO NFPA LIGHTNING PROTECTION STANDARD

National Fire Protection Association (NFPA) is a global nonprofit standards-writing organization devoted to eliminating death, injury, property, and economic loss due to fire, electrical, and related hazards. Their document, NFPA 780 – Standard for the Installation of Lightning Protection Systems, serves as the foundational standard for lightning protection systems in North America. Access to NFPA 780 is typically available to paying NFPA members or through a paid subscription. To view or purchase the latest version of the standard, please visit the NFPA’s official website at NFPA.org.

When determining how to incorporate lightning protection into new or existing structure designs, it is recommended that contractors, architects, and engineers engage the services of a specialty contractor with experience implementing the requirements of NFPA 780 and UL96A. However, here are a few questions we are often asked about standards for lightning protection systems and NFPA 780:

What is NFPA 780?

NFPA 780 is the industry-standard to follow when designing and installing lightning protection systems and components. NFPA 780 details the necessary considerations for installing lightning protection for ordinary structures and a variety of special applications. NFPA 780 is a consensus standard that has been maintained since 1904. It is updated every three years to incorporate technological advances and innovations in building materials. NFPA 780 provides the information required to protect people and property against fire risks and related dangers that can occur when a structure is exposed to a lightning strike.

Who Should Consider Lightning Protection?

According to NFPA 780, lightning protection is recommended for all types of structures, including commercial, industrial, public, and residential buildings. The standard includes additional guidance for special applications such as:

• Masts, spires, and flagpoles
• Facilities handling combustible or explosive dust
• Metal towers and tanks
• Air-inflated structures
• Concrete tanks and silos
• Rooftop helipads and guyed structures
• Structures containing flammable vapors, gases, or liquids
• Heavy-duty stacks and wind turbines
• Solar arrays, watercraft, and airfield lighting circuits

What determines the placement of lightning protection equipment on a structure?

NFPA defines zones of protection on a structure, based on the geometry of the structure and known behaviors of lightning as it approaches Earth. Lightning protection system designers utilize the rolling sphere method to help determine where air terminals or strike termination devices are required on rooftops or other parts of a building. To simulate how lightning might interact with a structure, lightning protection system designers utilize software to create a sphere with a 150-foot radius rolling over the surface of a building from all directions. Because it is assumed that lightning has an electrically charged field emanating approximately 300 feet from the bolt, lightning can strike in any location where the sphere touches the surface of a building. This includes roof edges and corners, roof-top equipment, and projections from the sides of buildings, such as balconies and gable ends.

Need Help Implementing NFPA 780?

For referrals to lightning protection specialty contractors with expertise in implementing NFPA780-compliant systems, please contact ECLE.