Evaluation of Fire Protection Piping in a DOE Performance Category 3 Structure

National Fire Protection Association (NFPA) Standard 13 [1] establishes rules and criteria to provide a reasonable degree of protection for life-safety and property loss concerns resulting from fire. These rules and criteria are typically established for commercial type facilities governed by the Uniform Building Code (UBC) [2] or a comparable code. In concert with this stated purpose, NFPA 13 includes provisions for protection against damage when subject to earthquakes. The effectiveness of these rules and criteria may be challenged, however, when the safety function is extended beyond life-safety and property loss to Natural Phenomena Hazards (NPH) evaluation where nuclear safety is also an important issue. This paper presents a criteria and methodology for the evaluation of fire protection piping involving grooved couplings in a Department of Energy, Performance Category 3, multi-story structure. The footprint of the structure is approximately 540 feet by 250 feet or 135,000 square feet. Grooved type couplings are used extensively in the fire protection industry and represent a non-integral type connection between adjacent piping segments, as opposed to welded connections. Due to the nonintegral type connection and the allowable axial and lateral spans permitted by the National Fire Protection Association (NFPA) Standard 13, these type couplings are sometimes considered to be “weak links” when subjected to earthquake loadings. The paper also presents a sample walk-down screening checklist focusing on criteria compliance as well as additional potential weak links that could result in additional seismic demands on the grooved couplings and the fire protection piping system.