8.15.19.4.1 When pipe schedule systems are revamped, a nipple not exceeding 4 in. (100 mm) in length shall be permitted to be installed in the branch line fitting.
8.15.19.4.2 All piping other than the nipple permitted in 8.15.19.4.1 and 8.15.19.4.3 shall be a minimum of 1 in. (25 mm) in diameter in accordance with Figure 8.15.19.4.2. 8.15.19.4.3 When it is necessary to pipe two new ceiling sprinklers from an existing outlet in an overhead system, the use of a nipple not exceeding 4 in. (100 mm) in length and of the same pipe thread size as the existing outlet shall be permitted, provided that a hydraulic calculation verifies that the design flow rate will be achieved in accordance with Figure 8.15.19.4.3. 8.15.19.4.4 The use of pipe nipples less than 1 in. (25 mm) in diameter shall not be permitted where seismic design is required on the system. Duane Johnson, PE Program Manager Division of the Fire Marshal (Support Contractor) Office of Research Services National Institutes of Health 301-496-0487 "Protecting Science - One Sprinkler at a Time" -----Original Message----- From: Jarron Gass [mailto:[email protected]] Sent: Friday, June 22, 2012 4:55 PM To: [email protected] Subject: 3/4" Pipe and Sprigs Folks, I am working on an older building, pipe scheduled system with ¾” pipe at the end of some lines as well as ¾” sprigs in some areas. As best we can tell, the bulk of the system is from about 1930. In NFPA13, 2011 edition it says the following: 22.4.1.2 Pipe sizes shall be no less than 1 in. (25 mm) nominal for ferrous piping and 3⁄4 in. (20 mm) nominal for copper tubing or nonmetallic piping listed for fire sprinkler service. This is referencing hydraulic calculations, but I seem to recall that there was a requirement somewhere in the standard to remove any ¾” piping and replace with 1”. If so, can anyone point me to the proper section and also, would that include the sprigs? It seems a little frivolous to remove the existing 1’-0” long sprigs and install an extra heavy close nipple with a ¾” x 1” reducing coupling, a short piece of 1” pipe and another reducing coupling. I appreciate any input. Thanks, Jarron Jarron J. Gass - J. & J. Fire Protection Co., Inc. 101 Powell Rd., Butler, PA 16002, (724) 586-6111, fax (724) 586-5151 emergency (724) 898-2481, <mailto:[email protected]> [email protected], <http://www.jandjfire.com> www.jandjfire.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20120622/28498e45/attachment.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: image001.gif Type: image/gif Size: 862 bytes Desc: not available URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20120622/28498e45/attachment.gif> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
