Sean, Since they discuss the use of mesh shelves in certain situations, they may have tested it in more ways than the one that was published. It might be worth contacting the technical services department of companies who make k25.2 ESFR's and see if they have any listings or endorsements that are closer to what you need.
Matt Grisé PE*, LEED AP, NICET II Sales Engineer Alliance Fire Protection 130 w 9th Ave. North Kansas City, MO 64116 *Licensed in KS & MO 913.888.0647 ph 913.888.0618 f 913.526.7443 cell www. AFPsprink.com -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, November 12, 2015 11:51 AM To: [email protected] Subject: RE: NFPA 13 plastics up to 25ft roof 30ft with K25 heads Matt, Yes, I agree with the point of not taking on responsibility, that is why I am trying to find a way to point to a published standard for our design choice. Yes we are also looking into FM standards as well for other possible design solutions. I guess I'm more pointing out that the wording of this section seems silly or lacking, and wondering if anyone else has run into this or if there should be an item #11 added that states "also usable in open racks". The handbook talks about how slatted shelves should be treated as solid shelves, hence why I believe they added this section. Since we can't use solid shelves with ESFR but fire tests showed slatted shelves work under very specific conditions. So taking it one step further, this design concept is for using slatted shelves, which is a worse storage arrangement compared to open racks, the design criteria should therefore be useable for open racks...Right? But I do not see a clear path for using K25 @ 15psi with open racks, even if all other line items are the same. So in essence, the way I read it, I build the racks and store the commodity exactly as 17.2.4 states and NFPA says fire tests proved this it works so we are good with it. I take out the slatted shelves and NFPA says we have no fire tests to prove this, so use K16 @ 35psi or K25 @ 50psi. How does that make sense? Thanks, Sean VG -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Matt Grise Sent: Thursday, November 12, 2015 9:44 AM To: [email protected] Subject: RE: NFPA 13 plastics up to 25ft roof 30ft with K25 heads I would not recommend using the adjustment you proposed. Without a very complete knowledge of how the sprinklers perform at various flows you are putting yourself in a risky position. If you can meet all of the special criteria of 17.2.4, then that should be fine. FM also has a design that uses k25.2 heads at 35psi. You might also check the listing documents for the sprinklers you want to use. They sometimes are updated with new approved criteria that are not in 13 yet. If you take on the responsibility of coming up with a new application for a product (in this case - k25.2's at 15.7psi) then you are also taking on a great deal of responsibility that it will work. Matt Grisé PE*, LEED AP, NICET II Sales Engineer Alliance Fire Protection 130 w 9th Ave. North Kansas City, MO 64116 *Licensed in KS & MO 913.888.0647 ph 913.888.0618 f 913.526.7443 cell www. AFPsprink.com -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, November 12, 2015 10:28 AM To: [email protected] Subject: NFPA 13 plastics up to 25ft roof 30ft with K25 heads Hi Forum, The following is based on NFPA 13 (2013). We have a roof height of 30ft, owner wants to store exposed unexpanded plastics in double row open racks up to 25ft. No solid shelves or open top containers. Looking at Table 17.2.3.1 my options are 14k@50psi OR 16.8k@35psi. We have low water pressure and the owner doesn't want a fire pump, he also wants ESFR, so we want to use K25@15psi. K25 doesn't come into play until storage is 25ft with a 40ft roof, but it requires 50psi. This pressure wouldn't work for what we are being asked to do. Using our K-factor formula equation the K14 and K17 heads require roughly 100gpm based on this table. If I run the K25 at 15.7psi I get 100gpm. Does anyone see this as being a problem? Is there an issue with the water not being able to penetrate the fire if the pressure is so low on a K25 while also being located so close to the top of the storage? To make this extra confusing If we read through section 17.2.4, it appears it will allow me to use the K25@15psi so long as I meet the 10 requirements. But this section is for when you want to use slatted shelves. Which would seem to delay heat travel and water travel compared to open racks. I'm sure I can convince the owner to follow these line an verse if he wants to do this storage arrangement, but it doesn't make sense to me that adding slatted shelves and wire mesh should be necessary. Since it specifically doesn't state that open racks are also allowed with this design, I might run into a reviewer that is checking boxes rather than trying to think it through. Thoughts? Thank you for your time an help. Thanks, Sean VG _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
