Sprinkler Age

September 2012

Sprinkler Age provides up-to-date information on the latest developments in the fire sprinkler industry. Readers call it “The Magazine” for technical information and rank it first in the industry.

Issue link: http://digital.turn-page.com/i/82410

Contents of this Issue

Navigation

Page 10 of 39

drawings with the exception of the existing eccentric and concentric reducer drawings. This should help avoid confusion when elbows and tee fittings are installed in the suction pipe for right and wrong configurations. The clearance needed for piping in fire pumps that pass through walls, floors, and ceilings is now provided in Section 4.17. This should not be confused with the seismic requirements noted in Section 4.28 for earthquake protection. For areas without earthquake designs, a clearance of not less than 1 in. is required around pipes that pass through walls, ceilings or floors of the fire pump room enclosure. The holes shall be sized such that the diameter of the hole is nominally 2 in. larger than the pipe. A pipe sleeve can also be used having a nominal diameter 2 in. larger than the nominal diameter of the pipe. Similar to seismic applications, no clearance is required if flexible couplings are located within 1 ft of each side of the wall, ceiling or floor. Fire pump rooms are required to be rated when located inside a building. As such, the clearance shall be filled with flexible material that is compatible with the piping materials and maintains any required fire resistance rating of the enclosure. Ground fault interruption is addressed for electric drives for fire pumps with new text provided as Section 9.1.7. This will read that no ground fault interruption means shall be installed in any fire pump control or power circuit and that no arc fault interruption means shall be installed in any fire pump control or power circuit. The annex clarifies that ground fault alarm provisions are not prohibited. This new information will also give Authorities Having Jurisdiction (AHJs) and code review personnel direct guidance and definitive reasons for rejection of any such protection schemes, methods, or equipment. The fuel supply requirements for a diesel driver received several changes. Section 11.4.4 will require that the valves located within the tank fuel supply line be locked in the open posi- tion. The original proposal included electrical supervision as an option but the committee indicated that locking the valve is the appropriate approach. Next is the issue regarding static electricity where new information will be in Section 11.4.6. The tank, pump, and piping shall be designed and operated to prevent electrostatic ignitions. They also shall be bonded and grounded. It was also clarified that when a double-wall fuel tank is provided that a containment dike is not necessary. In addition, if a double-wall tank is installed, the interstitial space between the shells of the diesel fuel storage tank shall be monitored for leakage and annunciated by the engine drive controller and the signal shall be of the supervisory type. The fuel level monitoring is already required by Section 11.4.2.4 where it indicates a means shall be provided within the tank for low fuel level signal initiation and new wording was added that it shall initiate a supervisory signal. Lastly, the sample pressure relief valve calculation form as Figure A.4.18.2.1 was modified to provide a better explanation of sizing the pressure relief valve. Section 4.18.2.1 allows the relief valve to be sized hydraulically where the new modified form is easier to follow. This article was not all inclusive of the changes to the 2013 edition of NFPA 20. There is too much information to include all the changes within an article format. Refer to the Report on Proposals and Report on Comments for further information or for further clarifications on the committee's and the submitter's intent usually described in the substantiation. n ABOUT THE AUTHOR: Tom Wellen is employed by AFSA in its Technical Services Department. He holds a bachelor of science in Engineering Technology, Fire Protection and Safety Technology from Oklahoma State University in Stillwater, Okla., and is actively involved with the National Fire Protection Association (NFPA) and Society of Fire Protection Engineers (SFPE). He has over 20 years of designing, testing, reviewing, and engineering experience. He is a registered fire protection engineer in the states of Texas and California. Wellen answers technical questions, serves on several industry technical committees, and assists with teaching AFSA's Beginning Fire Sprinkler System Planning School. He also serves on committees for the NFPA 13, NFPA 14, NFPA 20, and NFPA 101 standards. IMPORTANT NOTICE: As a member of the NFPA Technical Committee for NFPA 20, the following disclaimer applies. The article and its content is not a Formal Interpretation issued pursuant to NFPA Regulations. Any opinion expressed is the personal opinion of the author and presenter and does not necessarily represent the official position of the NFPA and its Technical Committee. Factory Tested Ready to Ship Easy to Install MODEL G5000 Advantages MODEL G3000 and Features FACTORY TESTS Hydraulic testing for pump flow and pressure. Hydrostatic pressure test in excess of 200PSI. FAST LEAD TIMES Large inventory and prompt turnaround allows for quick shipments. RESIDENTIAL WATER TANKS EASY INSTALLATION Floor and wall mount systems allow for flexibility of design and reduced installation time due to simplified mounting and wiring. S P D Incorporated 1167 Tower Road Schaumburg, IL 60173 (847) 882-9820 (847) 882-9825 FAX www.spdinc.com 13D RESIDENTIAL PUMP SYSTEM Sprinkler Age | September 2012 11

Articles in this issue

Links on this page

Archives of this issue

view archives of Sprinkler Age - September 2012