All very good points being brought up here and thank you for the insight.  This 
placard requirement is AHJ driven and being requested on older systems to match 
that being provided on all newer systems.  The last thing I would want to do is 
‘take over a design’ or prescribe operation of a system, even after a 
performance test.  That’s something I’m afraid I’d be doing if I was to infer 
anything less than measured flow to this placard.  No evidence on record 
anywhere of Standpipe Hydraulics, and not a surprise.  No record of 5 year 
performance testing in this particular building either, and also not a huge 
surprise.  There is some modeling required as pump discharge characteristics 
need to be worked back to the individual FDC’s (building has an original and an 
added one installed in the 90’s).  I will say I was on the fence with hiring a 
pumper crew which would have made this a simple as a current non high-rise, 
even using pre-’93 design, done this before, just not on an actual high-rise.

 

There are two signs referenced in NFPA 14 (2016) and methinks they’re being 
confused here.   There’s a sign at the FDC stating the required pressure 
prescribed by 6.4.5.2.2 and one for the hydraulic design summary (i.e. the 
“calc card”) per 6.8.  I think the FDC placard should state the required inlet 
pressure in order to make the minimum residual at the most remote outlets per 
the standard used as a basis of design (pre-1993), but I would VERIFY THAT WITH 
SERVING FIRE DEPARTMENT.    The hydraulic summary could actually be two cards, 
the original design (assuming it was calculated in 1986 and not pipe scheduled) 
and the current performance based on certification testing.  Again, consult 
with the AHJ; Mark’s comment is correct, that you’re essentially taking 
ownership of the design if you tag it with the performance test data.

 

The preceding is my opinion only and does not represent an interpretation at 
any level of the NFPA 14 standard or reflect the opinions of the members of the 
technical committee.  

 



 

From: Sprinklerforum [mailto:[email protected]] On 
Behalf Of Tom Duross
Sent: Friday, January 4, 2019 6:27 AM
To: [email protected] 
<mailto:[email protected]> 
Subject: FDC Placard

 

Trying this one more time, original never posted..

 

Did a 5 year Standpipe test on an older (1986) system with its own Fire Pump. 

Older ’83 BOCA (MA supplements, 14-1976): 500(1st) + 250 (2nd) plus 250 (for 
sprinklers).  1000 gpm Fire Pump in Basement.

Owner is asking me to provide a new placard for the 2 FDC’s.  OK.

Question:  Even this is an older 65# design system, it delivered almost 100# 
(to my surprise) from the 2 Standpipe’s FDV’s.

250 + 250 @ 83 from Roof Hydrant and 250@86 from top of other Standpipe.

Would you guys create an 83/86# design placard (this would match actual fire 
pump delivery) or a 65# design placard for the FDC’s?

I’ve hardly ever been asked to provide one for an older pre-100# system.  I 
usually end up running hydraulics anyway to work the  pump discharge back 
through the FDC piping to the inlet.  I’m inclined to lean towards stating 
something like “To match Building Fire Pump delivery of blah-blah-blah, a 
pumper delivery pressure of blah-blah is required at the FDC”.  (it won’t have 
the ‘blah’s in it)

I don’t want to incur any liability in scaling back residual pressures in a 
program versus actual.  

 

Tom Duross

 

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