Hmm. If the business portion of the occupancy is incidental to the residential use of the building, as in a cafeteria serving a dorm, then you drag over the couple items of #13 that 13R references for areas outside the dwelling units. If it's a restaurant serving the general public but located in a hotel, then the design is to #13 for the entire building- unless its two buildings within the definitions of building separation in your applicable building code. In either case, the riser is sized by the hydraulic demand.
I cannot imagine where you'd have a situation where the backflow preventor is dependent upon 13 or 13R. In 13D you could omit the BFP in certain instances, but that doesn't seem to be in your question. Why would the occupancy change the need for backflow prevention in your mind? Water still sitting there stagnant. glc -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Karen Purvis Sent: Wednesday, August 12, 2009 10:06 AM To: [email protected] Subject: Mixed occupancy These probably are questions everyone knows the answers to but I can't find the answers: 1. If you have a mixed occupancy (residential & Business) and your design is a 13R does your riser need to be at least a certain size or just large enough to serve the hydraulic area? 2. Because there is something other than residential in the building would I not need a backflow on the riser? Karen Purvis Senior Designer Facility Systems Consultants 713 South Central Street, Suite 101 Knoxville, TN 37902 ph.865-246-0164 fax 865-246-1084 _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
