ESFR - HYDRAULIC DEMAND 1

[SystemDesigner]

Hi guys

I have a query regarding how to take the
number of sprinklers in operation.
The rules state:

15.4.3 The design area shall consist of
the most hydraulically demanding area
of 12 sprinklers, consisting of four
sprinklers on each of three branch lines.

If this is my arrangement, which will
be the most demanding?
consider all measurements as uniform:

x1----x2----x3----x4------|-----x5----x6----x7----x8
|
|
x9----x10----x11----x12---|---x13----x14----x15----x16
|
|
x17----x18----x19----x20--|--x21----x22----x23----x24
|
|
|
|

 

[pipesnpumps]

I did a performance spec and preliminary hydraulic calcs for a tire warehouse once that was about the same size as SD2's (4" branches, 6"/8" mains.

The site loops was interesting. 12" with double lead-ins to each side of the header supplying the risers, with PIVs out away from the building, such that if there was a break it could be fed from either direction of the site loop. And oh yeah, redudant 250k gal tank and pump sets.

The head location rules for ESFR are brutal. For ventilation duct I went with a single plenum dropping straight through the roof, with sidewall diffusers.. No obstructions. I tell people you have to design the building around ESFR sprinklers, not the other way around..

 

[b1ueshift]

'I tell people you have to design the building around ESFR sprinklers, not the other way around..'

Yes I know what you mean. I was temping for a consultant once and the duct designer was shocked when I told him he had to move his duct because I needed the space for ESFR sprinklers. He was sure that duct designers should be higher up the food chain than sprinkler designers.