Not all 6 sprinklers but you have to determine the flow based on the SxL rule for the 3 sprinklers in that room.
Roland Huggins, PE - VP Engineering American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives Dallas, TX http://www.firesprinkler.org <http://www.firesprinkler.org/> > On Apr 30, 2015, at 9:21 AM, Jamie Seidl <[email protected]> wrote: > > Roland, > So if I am reading your response correctly, to use the provisions of > 8.6.2.1.2, I need to over look the 4 sprinkler design approach and > calculate the entire room? It's a little confusing because 11.3.1.2 says > that "Unless the requirements of 11.3.1.3 are met, the minimum required > discharge from EACH OF THE FOUR most demanding sprinklers shall be greater > of the following: (1) In accordance with minimum flow rates indicated in > individual listings. (2) Calculated based on delivering a minimum of 0.1 > gpm/sqft over the desing area in accordance with the provisions of 8.5.2.1 > or 8.6.2.1.2." A quick scratch paper write up we would be delivering .21 > gpm/sqft 6x21= 126 gpm/600sqft) because we still default to the minimum > flows, (in this case 21 gpm/sprinkler) > > On Thu, Apr 30, 2015 at 11:41 AM, Roland Huggins <[email protected] > <mailto:[email protected]> >> wrote: > >> very interesting question. To restate the question (since you have >> received answers on different nuances), we are looking at whether or not >> you can apply the small room rule to part of the sprinklers in the room >> (the room is 600 sf and has 6 sprinklers, you calculate the area per >> sprinkler by 600 / 6 for 100 sf per sprinkler then apply that to only 3 of >> the sprinklers to total 4 sprinklers with 1 from the adjacent room). I >> would say no. The current wording leaves that unanswered since it only >> tells you how to determine the area (as shown below). Keep in mind that >> the rule grew out of the 1500 sf minimum days so all sprinklers had to be >> included. This connection to the whole room is better indicated by the new >> text for the 2016 ed also shown below. You have to deliver 0.1 over the >> room aka the whole room. The issue you asked was not the basis for the >> change. Some were interpreting that the small room rule applied only to >> pendent sprinkler because it was located in 8.6. They had a point since as >> I preach often enough - LOCATION HAS MEANING. Nonetheless, it was the >> process that was being identified an not the sprinkler type but this is a >> much better approach. >> 11.3.1.3(2) Calculated based on delivering a minimum of 0.1 gpm/ft2 (4.1 >> mm/min) over the design area in accordance with the provisions of 8.5.2.1 >> or 8.6.2.1.2 >> >> 8.6.2.1.2 The requirements of 8.6.2.1.1 shall not apply in a small room as >> defined in 3.3.21. >> >> 8.6.2.1.2.1 The protection area of coverage for each sprinkler in the >> small room shall be the area of the room divided by the number of >> sprinklers in the room. >> >> 2016 ed - 11.3.1.3(3) In rooms or compartments 800 ft2 (74.3 m2) or less >> calculated based on delivering a minimum of 0.1 gpm/ft2 (4.1 mm/min) over >> the room or the compartment using the area of the room divided by the >> number of sprinklers in the room >> >> With this being an interpretation (and not something I can claim BUT IT’S >> EXPLICIT), I’m adding the NFPA caveat. As a TC member, this is my >> interpretation and not to be considered a formal interpretation of NFPA or >> any of its technical committees. >> >> Roland >> >> Roland Huggins, PE - VP Engineering >> American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives >> Dallas, TX >> http://www.firesprinkler.org <http://www.firesprinkler.org/> >> <http://www.firesprinkler.org/ <http://www.firesprinkler.org/>> >> >> >> > _______________________________________________ > Sprinklerforum mailing list > [email protected] > <mailto:[email protected]> > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > <http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org> _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
