The term NITMAM is an acronym meaning, Notice of Intent to Make a Motion.  
After 2nd Draft (Formerly ROC), a final draft of any standard is published for 
one last round of public review.  Since there is no opportunity to make 
comments for committee consideration, the last act of objection is to challenge 
a comment on the floor of the code hearing when the standard is up for adoption 
by general vote.   In order to raise your objection and be on the docket, you 
have to file a NITMAM to be heard on the floor.   After debate (often argument) 
the motion is put up for vote.  If it fails, the committee's revision stands in 
the final version but if it's upheld, then the language of the section being 
challenged reverts back to the previous edition and the committee's efforts on 
that item are vaporized.

SML

 




-----Original Message-----
From: Sprinklerforum [mailto:[email protected]] On 
Behalf Of Brad Casterline
Sent: Wednesday, September 17, 2014 11:57 AM
To: [email protected]
Subject: RE: Water Velocity

Steve,

I told the story you related to a coworker and he said "a good example of 
design by committee" (as to opposed to calcs, etc., I presume). What does 
NITMAM'd stand for?

NFPA 14, Table A7.8 (2013) made more sense after some thought, but instead of 
thinking in terms of "How far over the curve are we"? I did a couple source 
calcs and came up with, for the gated Y right on the 2.5" valve and
(2) 1.5x100' hose with that "100 PSI nozzle":
~400 GPM at 100 PSI at the SP, and
~330 GPM at 65 PSI at the SP--
a sort of rough Performance based design if you will.

Thanks,

Brad

 


-----Original Message-----
From: Brad Casterline [mailto:[email protected]]
Sent: Wednesday, September 17, 2014 10:32 AM
To: [email protected]
Subject: RE: Water Velocity

Thanks Duane. I'm all for using tables, but only after I fully understand how 
they were composed. I don't want to sound hyper critical, and I only had time 
for a quick glance (worried about getting busted), but I immediately started 
scratching my head over the table you cite.

Brad  

-----Original Message-----
From: Duane Johnson [mailto:[email protected]]
Sent: Wednesday, September 17, 2014 9:12 AM
To: [email protected]
Subject: RE: Water Velocity

Don't forget NFPA 14, Table A7.8 (2013) has some pre-calculated scenarios and 
required gpm, psi for different FD arrangements/nozzles/etc.
Requirements range from 120 psi to 168 psi.

Duane Johnson, PE
Design Manager
Strickland Fire Protection
301-474-1136 Office
301-455-0010 Cell



-----Original Message-----
From: Sprinklerforum [mailto:[email protected]]
On Behalf Of Steve Leyton
Sent: Wednesday, September 17, 2014 10:06 AM
To: [email protected]
Subject: RE: Water Velocity

No prollem.   You don't have to apply theoreticals however - Elkhart has
some friction loss data on line for hose and commonly used fittings.  If you 
assume the flow rate of 250gpm from a Class 1, common practice for many FD's is 
to put down a section of 2½" rubber suction hose and then connect a gated
wye that is sized for their preferred attack line, usually 1½" or 1¾".   If
you assume an 8' section of suction hose, 250gpm through a gated wye and 125gpm 
down a 100' length of lined synthetic 1½" hose, you get a loss of 45-55psi 
depending on variables.  Which supports the TC's finding of 150psi back in 
1993.  And which is why I (and others) have been pushing to include more 
forward language in both the standard and annex regarding "performance based" 
design.

SL


-----Original Message-----
From: Sprinklerforum on behalf of Brad Casterline
Sent: Wed 9/17/2014 6:54 AM
To: [email protected]
Subject: RE: Water Velocity
 
No problem Steve, thanks for the reply.

Until a few months ago, all I new about NFPA 14 was the written word, and that 
AHJs in Kansas City were not adverse to allowing 65 PSI at the top in lieu of 
100 (existing buildings). Any way, after having done a standpipe calc that 
included the loss for the valve, nipple and tee I thought what the heck why not 
include the nozzle and hose also. I totally guessed the coefficient of 
discharge of a 2.5" nozzle to be .75, which gave me K=92.2, Q=250, P=7.352, and 
flowing through 100 feet gave me about 62 PSI at the SP connection. That is 
when I posted the 'why 100 PSI' and got an excellent education (as usual on 
this Forum). For 250 through the 1.5" equipment though I came up with more than 
the 150 you cite (and I did not have to derive the PSI at the nozzle part). 
Then Monday I got a notice from AFSA that NFPA 14 is open for public comment, 
so naturally I started dwelling on "why raise the minimum 35 PSI when the 
reasoning being used would require raising it at least 85 PSI? Why not go all 
the way or leave it alone, since the FD will be there when they are being used 
anyway"?
The question I have now, and I should save it for Friday due to its laugh 
value, is; Do you foresee the 14 Technical Committee saying something like 
"OOps, let's back up to a simpler place and time, 65 it is again!"
Not only pump people, but PR valve people would have to tighten their belts, no?

:) Thanks again sir,

Brad Casterline     

-----Original Message-----
From: Steve Leyton [mailto:[email protected]]
Sent: Tuesday, September 16, 2014 8:20 PM
To: [email protected]
Subject: RE: Water Velocity

I've been buried today, so apologies for late answer.   I have a story, but
it's anecdotal and I wasn't in the room during the 1993 cycle.  However, the 
source of this information is VERY reliable and served on the 14 committee for 
a very long time.

By the 1993 cycle, selectable flow nozzles were displacing smooth bore/straight 
stream tips.  The first one, Select-A-Flow, was rated at
100psi.   Smaller diameter attack lines with shapeable tips were being
adopted nationwide, so the TC set about determining whether or not 65psi was 
the right number.  They determined that the correct number was 150psi, to allow 
enough loss in the hose and fittings to provide 100 at the tip.
Between ROP and ROC, there was an uproar as the only happy stakeholders were
pump manufacturers.   So in the second half of the cycle, they arrived at
100 as an increase that wouldn't get NITMAM'd off the floor of the code 
hearing.  It was political, not performance based.

If anyone's ever heard me do a presentation or just pontificate on standpipes, 
then you've heard me say that I think they should be designed for the equipment 
that the serving FD is using.  However, FD's have purchasing agents who stick 
to budgets and some cities change tips when the
time and price are right.   Changing equipment (and NOT failure of the PRV's
as commonly thought) was the main reason that inside attack streams couldn't
be developed at the Meridian Plaza fire.   

My opinion and someone else's story only ...

SML 




-----Original Message-----
From: Sprinklerforum [mailto:[email protected]]
On Behalf Of Brad Casterline
Sent: Monday, September 15, 2014 7:53 PM
To: [email protected]
Subject: Re: Water Velocity

BTW, while I got you, 14 is standpipes right? Your specialty, and open for 
public opinion? 
65 at the top was just right for the old 2.5 inch but 100 is inadequate for the 
modern, smaller packs-- any comments on that conundrum?


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