Ed: Per the Colorado cross connection Control Manual, any additive to potable water supply for fire protection requires a RPZ. The CCCCM references the 1997 UPC Specifically 603.4.18.3 "Where anti-freeze, Corrosion inhibitors or other chemicals are added to a fire protection system supplied from a potable water supply, the potable water supply shall be protected by one of the following: 1) RPZ assembly 2) RPZ/DC assembly"
Additionally from Appendix "D" of the CCCCM 1999, "Drain Flow Chart" It notes that drains which are required for all RPZ devices can discharge based upon operating pressure XX GPM and that drain sizes X" are able to accept XXX GPM. EXAMPLE: A 1" RPZ operating at a static pressure of 50PSI can discharge approx. 65GPM. A 2" floor drain can only flow 55 GPM, and a 3" 112GPM, so for a RPZ operating at 50PSI requires a 3" floor Drain. Example 2:A2.5" RPZ operating at 100PSI requires a 6" floor drain capable of 450GPM, because at that pressure the RPZ could discharge up to 400 GPM and a 5" floor drain can only take 350GPM. Please not specific discharge flows are available from some RPZ MFG.'s If they are less you can use them. Here's what the IPC 2006 says: 608.16.4 Connections to automatic fire sprinkler systems and standpipe systems. The potable water supply to automatic fire sprinkler and standpipe systems shall be protected against backflow by a double check-valve assembly or a reduced pressure principle backflow preventer. 608.16.4.1 Additives or non-potable source. Where systems under continuous pressure contain chemical additives or antifreeze, or where systems are connected to a non-potable secondary water supply, the potable water supply shall be protected against backflow by a reduced pressure principle backflow preventer. Where chemical additives or antifreeze are added to only a portion of an automatic fire sprinkler or standpipe system, the reduced pressure principle backflow preventer shall be permitted to be located so as to isolate that portion of the system. Thom McMahon, SET Firetech, Inc. 2560 Copper Ridge Dr P.O. Box 882136 Steamboat Springs, CO 80488 Tel: 970-879-7952 Fax: 970-879-7926 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ed Kramer Sent: Thursday, March 11, 2010 9:23 AM To: [email protected] Subject: Backflow protection on antifreeze system Anybody have a 2006 International Plumbing Code handy? I have a client who wants to use glycerine in a small antifreeze system. Nothing unusual about that. But he claims that by using food-grade glycerine he doesn't need an RP BFP and the associated expansion tank. I disagree, but don't have code references to back it up. The 2006 IPC is applicable. Thanks in advance! Ed Kramer Kramer Design, LLC Littleton, CO _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
