It seems to me that you have to flush a certain amount of water based on size of the main. The 10fps requirement can be calculated to gpm fairly easily. Then it is just a matter of flow, regardless of the size of the flushing connection. If you can get the flow out of a 1-1/2” connection (which I have my doubts), then great. You need a way of measuring it. Todd Williams
Fire Protection Design/Consulting Stonington, CT 860-608-4559 > > On Jan 28, 2025 at 5:51 PM, <John Denhardt > (mailto:[email protected])> wrote: > > > > > Please keep in mind if an underground supply a fire pump system, the minimum > velocity is 15 fps. While I do not agree with this requirement, iut is in > the book. > > > > > > > > > > > > > Thanks, > > John > > > > > > > > > > > > > > John August Denhardt, PE > > > > Vice President, Engineering and Technical Services > > > > > American Fire Sprinkler Association > > > > > m: p: > > 301-343-1457 > 214-349-5965 ext 121 > > w: > > firesprinkler.org (http://firesprinkler.org) > > > > > > > > > > > > > > > > > Kickstart 2025 with Top-TIer Training! > > > > > AFSA is offering a variety of training to start 2025 off right! Learn > design, hydraulic calculations, and ITM with our best-in-class training. > Learn more and register now for the February Beginning Design School > (https://www.firesprinkler.org/design), Sprinkler Hydraulics Course > (https://www.firesprinkler.org/programs/calculations/), Fire Pump ITM > (https://www.firesprinkler.org/calendarevent/fire-pump-itm-workshop-9/), and > Beginning ITM workshop > (https://www.firesprinkler.org/calendarevent/beginning-itm-workshop-6/)! > > > > > > > > > > On Tue, Jan 28, 2025 at 5:36 PM Brett Peters <[email protected] > (mailto:[email protected])> wrote: > > > > > _________________________________________________________ > > SprinklerForum mailing list: > > > > https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org > > To unsubscribe send an email to > > [email protected] > > (mailto:[email protected]) > > > > If this is for a new water main, the intent of this flush is to get rid of > > any debris and sediment that would be harmful to the sprinkler system, so > > if you have a 6" water service you need to achieve minimum flow for 6" pipe > > to adequately flush sediment and debris from the underground piping > > > > > > > > 10.10.2.1.3 The minimum rate of flow shall be not less than > > one of the following: > > (1) Hydraulically calculated water demand flow rate of the > > system, including any hose requirements > > (2) Flow necessary to provide a velocity of 10 ft/sec > > (3.1 m/sec) in accordance with Table 10.10.2.1.3 > > (3) Maximum flow rate available to the system under fire > > conditions > > > > > > 880gpm for 6" pipe, to produce 10 ft/sec > > > > > > > > If flowing a fire pump you would need to open 2 x 2 1/2" hose valves for > > that amount of flow so I'm very sceptical that a single 1 1/2" hose will > > produce the amount of flow required for a proper flush, personally when I > > have done a flush for a 6" water service we have flushed with 4" > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks > > > > > > > > > > > > > > > > Brett Peters > > > > General Manager Installation & Design > > > > Proudline Fire Protection Services Ltd. > > > > [email protected] (mailto:[email protected]) > > > > 780 490 7602 office ext 202 > > > > 780 490 7605 fax > > > > 780 777 0568 cell > > > > 780 718 2676 24h > > > > Visit us at www.proudline.ca (http://www.proudline.ca/) > > > > > > > > > > Proudline now offers ULc listed monitoring services, please contact > > [email protected] (mailto:[email protected]) for more information > > > > > > > > > > > > > > > > > > > > > > > > > > On Tue, Jan 28, 2025 at 3:11 PM Steve Leyton <[email protected] > > (mailto:[email protected])> wrote: > > > > > > > > > > > > > > > > > > > > Sprinkies: > > > > > > > > > > > > > > > > > > Section 6.10.2.1 (2022 edition) of NFPA 13 prescribes a minimum flow rate > > > of 10 fps for flushing, and Table 6.10.2.1.3 offers flow minimum rates > > > for different pipe diameters that will achieve that velocity. My > > > question is (the one that’s been posed to me by an inspector) is whether > > > or not there’s an absolute minimum flow rate in GPM based on size. A > > > contractor has proposed to flush a 4” UG through a 1½” connection with > > > “several hundred feet” of 1½” hose to a collection point. The > > > inspector is questioning (and I’m wondering also) if it is required or is > > > the intent to flush to at least the demand of the system, or some other > > > benchmark flow? For whatever it’s worth Table 6.10.2.1.3 > > > (10.10.2.1.3 in NFPA 24) starts at 2”, so I’m also curious if that > > > implies that 2” is the minimum allowable size for a flushing connection? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Steve Leyton, President > > > T | 619.255.8964 x 102 | www.protectiondesign.com > > > (http://www.protectiondesign.com/) > > > 2851 Camino Del Rio South | Suite 210 | San Diego, CA > > > 92108 > > > Fire Protection System Design | Consulting | Planning | > > > Training > > > > > > > > > > > > > > > > > > > > > > > > > > > _________________________________________________________ > > > SprinklerForum mailing list: > > > > > > https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org > > > To unsubscribe send an email to > > > [email protected] > > > (mailto:[email protected]) > > > _________________________________________________________ SprinklerForum > > > mailing list: > > > https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org > > > To unsubscribe send an email to > > > [email protected]
_________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org To unsubscribe send an email to [email protected]
