fire protection pipe min thickness
fire protection pipe min thickness
(OP)
what is the reference for calculating the required minimum thickness for piping used in a fire protection system?
Also, would I still apply a corrosion allowance for carbon steel pipe?
thanks
Also, would I still apply a corrosion allowance for carbon steel pipe?
thanks





RE: fire protection pipe min thickness
NFPA 11 Standard for Low-, Medium-, and High-Expansion Foam 2002 Edition
NFPA 11A Standard for Medium- and High-Expansion Foam Systems 1999 Edition
NFPA 12 Standard on Carbon Dioxide Extinguishing Systems 2000 Edition
NFPA 12A Standard on Halon 1301 Fire Extinguishing Systems 1997 Edition
NFPA 13 Standard for the Installation of Sprinkler Systems 2002 Edition
NFPA 13D Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes 2002 Edition
NFPA 13E Recommended Practice for Fire Department Operations in Properties Protected by Sprinkler and Standpipe Systems 2000 Edition
NFPA 13R Standard for the Installation of Sprinkler Systems in Residential Occupancies up to and Including Four Stories in Height 2002 Edition
NFPA 14 Standard for the Installation of Standpipe, Private Hydrant, and Hose Systems 2000 Edition
NFPA 15 Standard for Water Spray Fixed Systems for Fire Protection 2001 Edition
NFPA 16 Standard for the Installation of Foam-Water Sprinkler and Foam-Water Spray Systems 1999 Edition
NFPA 17 Standard for Dry Chemical Extinguishing Systems 2002 Edition
NFPA 17A Standard for Wet Chemical Extinguishing Systems 2002 Edition
NFPA 18 Standard on Wetting Agents 1995 Edition
NFPA 20 Standard for the Installation of Stationary Pumps for Fire Protection 1999 Edition
Good Luck!
-pmover
RE: fire protection pipe min thickness
Codes and Standards are voluntary (used at the discretion of the designer) UNTIL they are REQUIRED by the local jurisdiction - then they have the "force of law". Various Codes and Standards are required by a jurisdiction when they refer to them in the local (municipal, city, county or state/province) building Code. Regardless of what you read in discussion forums, you will have to look at the local building Code for the jurisdiction in which the piping system will be constructed to determine the piping design requirements.
I think you will find that in most USA jurisdictions the design of pressure piping systems (internal pressure of 15 psig or greater) of any type or use will refer to one of the ASME B31 Codes for Pressure Piping. Once you know the requirement of the building Code you should look for the Code section that provides the rules for pressure design (e.g., if the Code requires the use of B31.3 or B31.9 look under "Pressure Design"). Read the section in its entirety so that you will understand the requirements for mill tolerance, corrosion allowance, etc. In ASME B31.3 you would look at paragraph 304.
Regards, John.
RE: fire protection pipe min thickness
RE: fire protection pipe min thickness
"I can appreciate what you are saying, but in the case of small bore threaded connection, B31.1 says the min wall should be S-80. NFPA-13, 14, & 15 allow small bore threaded pipe using S-40 up to 300 psi."
OK. But first, B31.1 would only apply if your fire protection system were located in a power plant (the B31.1 requirement for the thicker wall piping would be to accommodate the loss of effective wall thickness due to threading - and B31.1 might also require "seal welds" over the threads). It is very unlikely that your jurisdiction would require B31.1 if the system is not in a power plant. If the system is not in a power plant, B31.3 (higher allowable stresses) and B31.9 would be more applicable. NFPA-13, 14, & 15 are ALSO national standards that by themselves do not have the "force of law". So, which Code to apply is really not your (or my) call to make.
Seems that the real issue here is what does your local jurisdiction require. The local building Code most likely has a separate section that includes requirements for fire protection systems. To get the correct answer, you are going to have to read the building code. You might also consider (as an alternative to reading through the building code) calling your local jurisdiction, explain to them the apparent contradiction in the Codes and asking them for their requirement. You could start by looking at the National Board's site to find the telephone number for your State/Province Chief Inspector at:
http
Chief Inspectors are usually very approachable and your call would demonstrate your desire to "do the right thing" so the Chief will be glad to help you.
Regards, John.