Spray sprinklers are "control mode" sprinklers, but we generally don't call them CMDA. There is now a defined category called Control Mode Specific Application (CMSA) sprinklers, which are essentially spray sprinklers that have been specifically listed as to the number of sprinklers that must be proven and the minimum starting pressures, based on K-factor, height and type of storage. In the 2013 edition of NFPA 13, Large Drop sprinklers are now grouped with CMSA sprinklers. The chart you are referring to in NFPA 13, 2007 is a prescriptive for spray sprinklers.
Steve Leyton -----Original Message----- From: sprinklerforum-boun...@firesprinkler.org [mailto:sprinklerforum-boun...@firesprinkler.org] On Behalf Of Jeremy Frazier Sent: Tuesday, February 12, 2013 7:27 AM To: sprinklerforum@firesprinkler.org Subject: CMDA vs Standard Spray Is there any difference between a CMDA sprinkler head and a standard spray sprinkler? If so, do the CMDA sprinklers have to be specifically listed for the storage class? For instance, I am designing a rubber tire storage area with 10'-0" storage height. If you go to NFPA 13 2007 18.4 it says "Ceiling Systems. Sprinkler discharge and area of application shall be in accordance with table 18.4(a) for standard spray sprinklers. Large drop and ESFR sprinklers shall be in accordance with Table 18.4(C) and Table 18.4 (d) Respectively." Table 18.4(a) title is "Table 18.4 (a) Protection Criteria for Rubber Tire Storage Using Control Mode Density-Area Sprinklers" It appears NFPA is using CMDA and standard spray sprinkler as the same thing. I did not find a definition in NFPA of what a CMDA actually is. To add to my confusion, I have seen sprinkler cut sheets that are specifically called out as CMDA sprinklers, and cut sheets that manufacturers tell me are CMDA sprinklers but have no reference on the cut sheet to being CMDA. Am I just over thinking this? Jeremy Frazier Cavalier Fire Protection Inc. Office: (571)-931-1004 Fax: (571)-931-1010 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attach ments/20130212/8d606581/attachment.html> _______________________________________________ Sprinklerforum mailing list Sprinklerforum@firesprinkler.org http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list Sprinklerforum@firesprinkler.org http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
