Good questions! Where sprinklers are required, a max deflector distance would be required, times sq ft would give you cubic. Where no sprinks are req'd, cubic is given. This is the only thing I can think of, but I messed around with the numbers and came up empty.
-----Original Message----- From: Todd Williams [mailto:[email protected]] Sent: Monday, May 24, 2010 8:10 AM To: [email protected] Subject: Composite wood joist confusion. I need some sort of a clarification on something in NFPA 13 (2002). Section 8.6.4.1.2 (4) calls for composite wood joists to be fire stopped so that the areas do not exceed 300 square feet. This is for sprinklers below exposed CWJs. When you get to section 8.14.1.2.6 (CWJs with ceiling below), it talks about joists fire stopped into volumes of 160 cubic feet. (1) Why do they reference a square footage for fire stopping for exposed CWjs and a volume for CWJs above a ceiling? (2) How is the square footage calculated, length of channel x width of channel? This carries through to 2010. Todd G. Williams, PE Fire Protection Design/Consulting Stonington, CT 860.535.2080 www.fpdc.com _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.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 [email protected] http://fireball.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)
