Obstruction to Discharge !!!
Obstruction to Discharge !!!
(OP)
Is there any NFPA 13 code section I can refer to avoid sprinkler heads underneath the sunshade? (Please see attached sketch)
A room, 11'-0" ceiling height, light hazard occupancy has aluminum sunshade in the window. The sunshade is 3'-10" below the ceiling and extends 2'-11" into the room from the window. NFPA 13 2010 Section 8.6.5.3.3 states, sprinkler shall be installed under fixed obstructions over 4ft. Can any of the sections be applied to avoid sprinklers underneath the shade?
The maximum allowable distance of deflector above the bottom of obstruction per table 8.6.5.1.2 is 35 in. The distance from the ceiling to the sunshade is 46 in. also "D" in Fig. 8.6.5.1.2(b) is greater than 30" so I can't apply thee basic obstruction rules.
A room, 11'-0" ceiling height, light hazard occupancy has aluminum sunshade in the window. The sunshade is 3'-10" below the ceiling and extends 2'-11" into the room from the window. NFPA 13 2010 Section 8.6.5.3.3 states, sprinkler shall be installed under fixed obstructions over 4ft. Can any of the sections be applied to avoid sprinklers underneath the shade?
The maximum allowable distance of deflector above the bottom of obstruction per table 8.6.5.1.2 is 35 in. The distance from the ceiling to the sunshade is 46 in. also "D" in Fig. 8.6.5.1.2(b) is greater than 30" so I can't apply thee basic obstruction rules.





RE: Obstruction to Discharge !!!
Should not be a big design issue
RE: Obstruction to Discharge !!!
However, I would say it doesn't need additional heads because the shades are not >48" wide. See 8.6.5.3 "Obstructions that Prevent Sprinkler Discharge From Reaching the Hazard". That is the section that applies in my opinion. Think of the shade as a cable tray or duct. You wouldn't put heads under a 2'11" wide duct. An AHJ might fight you on that, though because water can't pass over the shade only under it, and only under if the head is ~11' from the wall (see figure A.8.5.5.1) need 8' distance to throw under something 4' below the head. If you placed it carefully and did that, they'd really be out of line not allowing it.
As it stands you could plausibly claim 2'11"<4'0" so no sprinklers are required.
Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.
RE: Obstruction to Discharge !!!
The light shelf need to be reduced to 16" max. depth to remain at the current elevation or else the elevation will have to be increased.
RE: Obstruction to Discharge !!!
Will look at the book to see if there is something
Can you use small room rule or is room to big???
Or use extended coverage head???
Need to look at the book may be a non issue
Will get back
RE: Obstruction to Discharge !!!
RE: Obstruction to Discharge !!!
The question is "Does NFPA 13 require every square inch or square foot of floor space to be physically wetted by spray from a sprinkler?"
Attached is an interesting answer by Ken Isman http
RE: Obstruction to Discharge !!!
going by the reference you stated """Section 8.6.5.3.3 states, sprinkler shall be installed under fixed obstructions over 4ft.""
Unless I am missing something the shade is only 2'11" inside the room
so no problem!!!!!!!!!!!
RE: Obstruction to Discharge !!!
RE: Obstruction to Discharge !!!