Looking at a building that has ESFR fire sprinkler protection. Half is being used as open office area. They are installing circular ducts from 32" to 84" diameter with the top of the duct approximately 36" below the ESFR deflector (right below the roof trusses). In reading 8.12.5.3 2013 edition, in most cases if not all, Table 8.12.5.1.1 cannot be met, so sprinklers will need to be installed under the ducts. With the duct being 32" to 84" diameter, where would the fire sprinkler be placed? Per NFPA 13 is a flat barrier required to be installed under the circular duct? FM give you a guideline, but 13 does not. Owner does not want the ESFR sprinklers change out, so again where would you place the sprinkler and/or is a flat barrier required by NFPA 13? (With a flat obstruction you can either be under it or within so many inches of the end, but a huge diameter obstruction, is it the edge, center ,etc.?)
Second thought, since this is no longer a storage application, can you apply the standard spray sprinkler obstruction rules? (This still does not state where to install the sprinkler below the obstruction, but you could eliminate the obstruction less than 48".) Thanks, Gregg Fontes Cen-Cal Fire Systems, Inc. 209-334-9119 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
