Thanks for the background and clarification Steve, I appreciate it. Jamie Seidl NICET SET #107472 Century Fire Protection<http://www.centuryfp.com/> | General Manager 3600 Woodpark Blvd. Suite G Charlotte, NC 28206 PLEASE NOTE NEW ADDRESS ____________________________________________________________________ p 704 888 3473 | m 704 650 0033
From: Steve Leyton <[email protected]> Sent: Wednesday, July 3, 2024 11:36 AM To: Discussion list on issues relating to automatic fire sprinklers <[email protected]> Subject: [Sprinklerforum] Re: 2013 NFPA 14 7.5.3 External Email: ONLY open links/attachments from known safe sources Damn you guys - I'm not on vacation and was awake when Rick pinged as well. This may come as a shock but we need our morning coffee and time to make breakfast and #2 on the West Coast same as y'all. As they say, if you're using an older edition of a standard want to confirm or clarify the committee's intent on a particular issue, look at the most current edition of that standard. Moving from 2013 to 2016, there was a subtle change in 7.5.3 where it was revised to say, "Where wet standpipes are interconnected...", so that clarifies the intent that it be applied to wet only. There's also 7.5.4 that states, "Dry standpipes shall have only a single level of interconnection", so looping a dry manual was taken off the table. Jump ahead to 2024 and (renumbered) 9.4 has been simplified. 9.4.3 still restricts dry standpipes to a single interconnection but overall, you can interconnect at any level (unless the system is supplied by a rooftop tank), no check valves are required, and with the AHJ's approval standpipes don't need to be interconnected at all. When the committee opened discussion of the check valve requirement this past cycle, we couldn't figure out why that was even in the standard. It's been there for so long that it became inertial at some point, I guess. I/we have gone over this quite a bit and, so long as there are sectional valves that enable isolation of a standpipe, we couldn't figure out why a check was required. But I'm also concerned about looping manual standpipes because if there's a hydraulic advantage but the system has to be sectionally isolated, then a dead-end calc' should be the basis of design. I'm a proponent of the KISS theory. (When Caputo and I were advocating and lobbying city building and fire officials for residential fire sprinklers back in the 80's he used to say that the best and simplest residential sprinkler system was just pipe, fittings and sprinklers and no extraneous valves or connections. I agree with that approach, especially with manual standpipes.) There are scenarios with multi-zone systems where interconnection to supply a higher zone is one of the approved arrangements, but if I'm the AHJ, I'm down with a single interconnection and no check valves, wet or dry. SL Bright eyed and bushy tailed, whatever that's supposed to mean From: Jamie Seidl <[email protected]<mailto:[email protected]>> Sent: Wednesday, July 03, 2024 5:44 AM To: [email protected]<mailto:[email protected]> Subject: [Sprinklerforum] FW: 2013 NFPA 14 7.5.3 Quick question on a holiday week. 7.5.3 states that "Where standpipes are interconnected at the top and bottom, check valves shall be installed at the base of each standpipe to prevent circulation". Is this requirement intended to apply to manual dry standpipes? NFPA 14 does not appear to make a distinction in this case, but if they're intended to prevent circulation, I would imagine that is not a concern with a manual dry system. Steve, are you on vacation yet? This one is up your alley. Thanks for your time. Jamie Seidl NICET SET #107472 Century Fire Protection<http://www.centuryfp.com/> | General Manager 3600 Woodpark Blvd. Suite G Charlotte, NC 28206 ___________________________________________________________________ p 704 888 3473 | m 704 650 0033 Facebook<https://www.facebook.com/CenturyFP> LinkedIn<https://www.linkedin.com/company/century-fire-protection> Twitter<https://twitter.com/centuryfp>
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