I know that for a 13R sprinkler system the underground supply has to be pressure tested for 2 hours, however in the 2007 edition of NFPA 13R I can't find where it states that. In section 6.4.2 it talks about testing the aboveground piping, but omits the underground supply and I can't find it any place else in the standard. It might be in the IFC, but I can't find it.

I thought there used to be a catch-all that stated that if it wasn't addessed in 13R you reverted to 13, but alas I can't find that either, figures huh?

I'm sure its right in front of me. Any ideas?

Since it seems like the standard does not think there will be anything but city main pressure on the pipe, there is no need to hydro it.

And also appears you can use any pipe

And possibly tapped of the domestic.


A.5.2.1  This standard anticipates that the water supply for the system is in compliance with the governing plumbing code for the jurisdiction. It is intended that any pipe material or diameter permitted for multiple-family dwellings in the plumbing code and satisfying the hydraulic criteria of NFPA 13R is considered to be in compliance.
Any type of pipe or tube acceptable under the plumbing code for underground supply pipe shall be acceptable as underground supply for the fire sprinkler system when installed between the point of connection and the system riser.


also do not see nfpa 24 referenced

B.1.1 NFPA Publications. National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169-7471.
NFPA 13, Standard for the Installation of Sprinkler Systems, 2007 edition.
NFPA 13D, Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes, 2007 edition.
NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, 2007 edition.
NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, 2002 edition.

In my part of the world, 13R usually has the municipal supply to the building and is installed by the mechanical contractor who is responsible for whatever testing is to be done including filling out the sheets as required by the sprinkler system acceptance testing for above ground piping that the piping has been properly flushed. The 13R "sprinkler system" starts at the check valve after the domestic tie in within the building, and is all that is required to be tested to 200 psi. In the 2008 13, chapter 10, Underground Piping, under 10.10 Testing and Acceptance, though there is an area in Fig 10.10.1 Contractors Test Certificate that can be filled out for hydrostatic testing, 10.10.2.2.1 states 'All piping and attached appurtenances subjected to system working pressure shall be tested...' Therefore if your "system" is shared with a domestic line into the building and you have a backflow preventer or some other check valve assembly installed, your system starts there and it doesn't matter who installed the underground. It wouldn't be subject to NFPA's requirements for hydrostatic testing.

On the other hand if you are doing a subdivision for example and are running mains to all the buildings and boosting the pressure with fire pumps, reducing the domestic tie ins with PRV's, then I believe you might be required to test to 200psi or 50psi in excess of system pressure, whichever is greater.

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