The mysterious sprinkler "heads" in NFPA 13, Chapter 21

[fpst]

In NFPA 13 2010, there are 17 instances of sprinkler "heads". All of these instances are in Chapter 21 "Special Occupancy Requirements".

It appears that calling sprinklers by the name of sprinkler "heads" has been wiped out in the official part of NFPA 13 in every chapter except Chapter 21, and I'm just wondering.. why? Is there some special reason they call sprinklers by the name of sprinkler heads in Special Occupancy?

I'm guessing that Chapter 21 originally was from another standard and got slapped in NFPA 13 or something?

Interestingly, 35% of the topics in this forum have someone referring to sprinklers as sprinkler "heads", while this practice is virtually nonexistent in NFPA 13 except in Chapter 21.

It makes me wonder what mysterious phenomenon is happening here in the niche fire sprinkler world.

 

[LCREP]

How long have you been wondering about this? I hope it has not kept you awake at night too long.....LOL

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!

 

[cdafd]

Thought this question was asked before. Will have to look

 

[Sdpaddler50]

Isnt the phrase "sprinkler head"? IE, you can say sprinkler, or head and be grammatically correct.

 

[fpst]

Well, it's 12:41 AM and I can't sleep because I'm still thinking about it (sarcasm)

I've got a new theory, maybe it's because "sprinkler head" is superfluous. You can just call it a 'sprinkler' and the head isn't necessary to explain it.
Also, it could be because "sprinkler head" has two possible interpretations, if you use the alternative definition of "head" which is a hydraulic measurement it could lead to confusion, especially considering there is no reason to tag "head" on the end of "sprinkler" any way, for explanatory purposes.

@LCREP

In all seriousness, I'm making myself read through NFPA 13 everyday and I'm not even getting to design sprinkler systems yet, so suffice it to say that it's booooooring and the only way my mind can stay awake is if I notice these little things and make a game out of it..

 

[cdafd]

OTHER head references:::




Chapter 21 Special Occupancy Requirements (-)




21.4 Spray Application Using Flammable or Combustible Materials.

system, a preaction system, or an open-head deluge system, whichever is most appropriate for the portion of the spray operation being protected. [33


21.7 Nitrate Film.

protected per sprinkler head shall not exceed 64 ft2 (6 m2) with sprinklers and branch lines not being more than 8 ft (2.4 m) apart. [40


21.16 Standard for Ovens and Furnaces.

related equipment, the use of closed-head sprinkler systems shall be prohibited and only deluge sprinkler systems shall be used where the following condition exist: (1)In equipment where temperatures can


21.21 Water Cooling Towers.

lends itself to either closed- or open-head systems, the following systems shall be permitted to be used: (1)Wet-pipe(2)Dry-pipe(3)Preaction(4)Deluge [214


21.22 Standard for the Construction and Fire Protection of Marine Terminals, Piers, and Wharves.

) The following design and installation guides shall apply where pendent sprinklers in the upright position or old-style sprinklers are to be utilized: (1)The maximum coverage per sprinkler head shall be


21.36 Coal Mines.

constant flow of water with all heads functioning for a period of 10 minutes.(3)The sprinkler head activation temperature shall not be less than 65.6°C (150°F) or greater than 148.9°C (300°F). [120



Chapter 22 Plans and Calculations (+)




22.3 Hydraulic Calculation Forms.

lengths for fittings and devices(8)Friction loss in psi/ft (bar/m) of pipe(9)Total friction loss between reference points(10)In-rack sprinkler demand balanced to ceiling demand(11)Elevation head in psi (bar



Annex A Explanatory Material (+)


A.9.2.1.3.3.4

. Relocation of this device should only be performed by qualified and/or licensed individuals that are aware of the original system design criteria, hydraulic criteria, sprinkler head listing parameters, and

 

[fpst]

Those are the ones I was talking about (Chapter 21). The only way you found one in chapter 9 was in the annex as I said in my original post, I was talking about the official part of NFPA 13 (everything but the annex). In the annex there's actually 2 instances of it being referred to as a head that aren't in the chapter 21 annex. And the one you posted about chapter 22 is talking about elevation head which is different, isn't it? That's the 'confusing' part about it, you sometimes can't tell if it's talking about the elevation of the sprinkler, or the hydraulic measurement!

It was interesting to me that there were two instances in the annex though, because it must have meant that at some point, NFPA 13 used to refer to them as sprinkler "heads" in the official part, and then they took the time to remove it but missed a couple in the annex.

 

[stookeyfpe]

As someone who works on code books and related publications, nothing sinister is happening. Instead, what has probably happened is that the NFPA 13 TC has reorganized the standard in the past few code cycles and no one has submitted a change proposal to update this chapter to the current terms. Chapter 21 is a place holder so other TCs automatic sprinkler requirements have a place to land their requirements so correlation is achieved (which is required by ANSI). No code change proposals from the other TCs have been submitted so nothing has changed. I'm fairly sure the folks on the TC for cooling towers haven't looked at the terms they selected 20 years ago for sprinkler protection.

 

[LCREP]

FPST,

You may want to buy the NFPA 13 handbook it gives you a lot of good background on the code and what the committee was thinking when they wrote the various code sections.
WARNING IT IS STILL BORING!!!.....LOL

If you are near NJ check out "hands on" fire protection training at

http://www.chubb.com/lcu

they try to make sense of the codes.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!