Mike, If you have the handbook for 2007, the commentary text elaborates that the intent of 22.4.4.6.3 extends to permanent or temporary obstructions, specifically mentioning overhead garage doors.
Marc Walter Sprinkler Design Services -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Mike Hill Sent: Monday, October 07, 2013 9:33 AM To: [email protected] Subject: Sprinklers Below Overhead Doors Question: Are sprinklers below overhead doors required to be included in hydraulic calculations? When I first started in the industry, I was told that heads below overhead doors were required to be included in the hydraulic calculations. The reason being, it was a temporary obstruction. The door could be up or down if a fire broke out, unlike a large duct which was a permanent obstruction. I was recently questioned by a FPE as to why I included heads below the door in a hydraulic calculation. I explained my reasoning to him and he accepted it. In his eyes I had proven a more demanding situation than was needed so it didn't affect his stamping the plans. Flash forward a few weeks and to a different project. I now have a much larger operating area and removing these (11) heads from the calculation would help it greatly. I am providing protection for a firehouse expansion on a military base. This calculation is in the apparatus bay. UFC requirements are in effect, ceiling height over 20'-0" and it is sloped enough to require the 30% increase. The majority of the piping being calculated is existing and to remain as is (if at all possible). Using 2007 Edition of NFPA-13 (only one I have handy at the moment). 8.5.5.3.1 Specifically mentions overhead doors need protection below. No problem here. 22.2.2.6.3 Does not mention overhead doors when providing situations where sprinklers can be omitted from hydraulic calculations. The wording in these sections seems to support what my mentors instilled in my soft pliable mind all those years ago. What says the forum? Mike Hill _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
