Travis, question for you, RE: 11.2k+ in Storage Applications 1

[JerSPK]

I was going to reply in the other thread but it seemed like it might get lost in the shuffle of the "code memorization" topic.

Was section 12.6 detailing the K-factors in storage applications new in the 2007 edition? I have the 2007 and 2010 (and 1999) editions, but we somehow lost the 2002 and 2004 editions. The annex of the 2007 edition goes into a good amount of detail about the more recent fire tests conducted to include the K-Factor changes so I'm thinking that was the year it was added?

The reason I ask is we have designed a few storage upgrades in recent years using 8.0k heads with over .35 density. I checked two of the most recent ones and both villages follow the 1999 edition. Still, it was a bit of a shock since it was a section I had obviously glossed over many times but never even considered. The Chicago area is notorious for hanging on to old codes for ages (City of Chicago itself follows 1994.....) so I'm guessing that we've never done the above in a town where it was against the standard (and thus why it was approved). Still, it reinforces your practice of always reading through new editions carefully when they come out. We had used the same design when I first started in '04 and it's too easy to think that because it was used before it can be used again.

 

[TravisMack]

It came out in the 2002 edition if I recall correctly. The 1999 edition incorporated 231 & 231C among a few others into NFPA 13. Then in 2002, there were some more things such as this k-factor requirement for storage.

This just made me think of another example. In the 2002 edition of 13, it states that the storage sections do not apply to roofs or ceilings with a slope >2:12. I have had to be the bad guy on several occasions to tell some one that they can't store in a building because of the roof slope. The AHJ has been contacted on these occasions and backed us up as well. He tells them to either put in a ceiling to flatten it out, or do full scale fire testing.

I think this is pretty common, to do things the same way as in the past. "If it ain't broke, don't fix it." I have actually picked up a new customer because I was doing some review work for them and pointed out how they missed some really stringent attic requirements. The main guy at the company had not really been required to update his knowledge of NFPA 13 since the 99 edition. Well, in 2002, the attic criteria changed DRASTICALLY.

This should be a good reminder, that even though NFPA 13 can be a great cure for insomnia, it is something that we should all do when the new edition comes out. If nothing else, at least read all of the items with a bar in front of them.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[JerSPK]

Beyond the worry of actually designing and installing something that doesn't meet the standard, part of me isn't feeling well about the reduced protection we've installed a few places. It meets the adopted code and NFPA edition required, but that's only because the municipality is slow to update. As the professional we (should) know from the more recent standards that the 11.2k+ sprinklers will provide better protection to our client. Is it ethical to sell a client less protection just because their municipality is behind the times?

The few jobs that we've used the 8.0k sprinklers in have been warehouse upgrades where all of the existing outlets were 1/2" with existing 5.6k sprinklers. The calculations work out using 1/2", 8.0k sprinklers, and the owner saves a lot of money by not having to replace every existing fitting (which would usually be on top of the cost to grid the existing trees). The 1999 standard approves it so the design is approved, but is it right if we know it is sub-par protection?

This is the kind of thing that makes me feel sick inside, and will definitely change the way I study the new editions.

 

[TravisMack]

Jer:

I agree with you on that aspect. It is challenging when you are required to meet the 1999 standard as that is what your competition is doing, but we now know that the newer standards have provided better clarification.

Along the same lines, what if you have a flat combustible concealed space with less than 36" of clearance - common between floors. The 1999 edition lets you use standard spray sprinklers in that area. The 2002 and newer requires specially listed combustible concealed space sprinklers. These sprinklers then require draft curtains and possibly wired in insulation (if you have TJI construction). You will not get the project if you bid with concealed space sprinklers. But, you are not wrong if the required standard is 1999 edition. However, the standards are just a minimum. It is a catch-22. I always try to apply the newest standard, even in jurisdictions using older standards, as long as the new does not contradict the old. I mean that if the new is just a different k-factor, or something along those lines, I try to just go that route.

Along the lines of your original question, I believe you can now get a 1/2" NPT x 11.2k sprinkler for retrofits like you described. I find that is rare to work as often times if you have 1/2" sprinklers, the spacing is greater than 100 sq ft that is req'd for densities of >0.25 gpm / sq ft.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[JerSPK]

Travis, I actually have never seen a 1/2" 11.2k for use with density/area designs before. I've used a 1/2" 11.2k Large Drop from Viking a couple times now, but the pressure requirements of the large drop don't always make it the best option. I'll have to look around a bit more for other brands that may have the above for the density/area application.

Thanks for the responses, Travis. I've been picking up valuable information from this board for a while, but last night really caught me by surprise. It just shows that you can never get too comfortable and simple discussion can offer valuable insight even when you're not looking for it.

 

[TravisMack]

Check out this data sheet:

http://www.tyco-fire.com/TD_TFP/TFP/TFP342_03_2007.pdf

This is just a standard spray upright so you can use with area/density. The TY5851 is the 1/2" NPT.

I am happy to help. It is true that you can never get too comfortable in this business. I am sure the next edition of NFPA 13 will shake us all up again.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[JerSPK]

...now I really need to slap myself around. I've not only used that sprinkler in the past, but even just recently used it in a preliminary design. Those instances either were using existing 3/4" outlets or was a new installation so it wouldn't have made a huge difference, but the fact that I'm using the heads off and on and I never even noticed it came in 1/2" is...not good! Thanks again for another heads up, this one will definitely help in the future!