TechNotes Issue # 391

Best of February 2018
Following are a dozen questions answered by the engineering staff as part of the NFSA’s Expert of the Day (EOD) member assistance program during the month of February 2018. This information is being brought forward as the “Best of February 2018.” If you have a question for the NFSA EOD (and you are an NFSA member), send your question to [email protected] and the EOD will get back to you.
It should

TechNotes Issue # 391

Question 1 – Velocity Limitations
You note that FM Global insured projects limit flow velocities in sprinkler systems.
Does NFPA 13 limit the velocity of water flow through a pipe?
Answer: The answer to your question is “no.” NFPA 13 does not set a limit on flow velocities in sprinkler systems. When Hazen-Williams or Darcy-Weisbach calculations are performed, NFPA 13-2016 section* explicitly states that flow velocity is not to be limited unless required by another NFPA standard.* Unless

TechNotes Issue # 390

When is Steel Pipe Smaller Than 1-Inch Acceptable in NFPA 13?

If you ask someone in the fire sprinkler business, they can probably tell you that steel pipe used in sprinkler systems must be at least 1-inch in diameter. They may even add that it can be as small as 3/4-inch for copper tubing or listed brass, stainless steel, or nonmetallic pipe. They may or may not be aware

TechNotes Issue #384

Question 1 –  Main Drain Testing
Does main drain testing in a multi-story building need to occur at the riser where the underground enters the building, at each floor control valve, or at the auxiliary drain on each floor?
Answer:  The answer depends on whether this is acceptance testing in accordance with NFPA 13, or part of testing procedures in accordance with NFPA 25. These two standards look at the testing differently due to

TechNotes Issue #382

Question 1 – Heat Treatment for Bedbugs
A thermal termite control process has been proposed for use in residential buildings protected with fire sprinkler systems. It has been noted that this method has been used in California and is gaining popularity on the East Coast.
Will the high temperature used in this process, typically 120° F to 140° F, affect sprinkler systems?