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shelve storage 16 feet high

shelve storage 16 feet high

shelve storage 16 feet high

(OP)
nfpa 13 2002

20,000 sq ft building

retail

9000 sq ft of shelve storage as defined by 3.9.17

spread out through the retail area

class I-IV commodities

Any certain section I should be looking at??

Is there a design criteria for this set up or look at the closetest thing in 13??

they are specing tyco k17-231 heads 16.8 k factor


RE: shelve storage 16 feet high

I would look at NFPA 13, 2002:

12.2.2.1.1  Protection for Class I through Class IV commodities in the following configurations shall be provided in accordance with this chapter:
(1)     Nonencapsulated commodities that are solid pile, palletized, or bin box storage up to 30 ft (9.1 m) in height
(2)     Nonencapsulated commodities on shelf storage up to 15 ft (4.6 m) in height
(3)*     Encapsulated commodities that are solid pile, palletized, bin box, or shelf storage up to 15 ft (4.6 m) in height

This states you can only get 15' of shelf storage.  Also, the Design Criteria section of the K17-231 data sheet does not provide a criteria for Shelf Storage in excess of 15'.  So, it looks like there may have been some special testing involved, or you need to dig deeper as to how they are getting 16' of shelf storage.  OR, I may be totally missing the boat on something, which would be very possible for a Friday.

Travis

RE: shelve storage 16 feet high

Travis is correct. Unless substantiated by fire tests I don't see how they can get above 15-0 AFF.

If memory serves me correctly, the 15-0 AFF value was the maximum reasonable height for storage shelves when the high piled storage fire testing was performed in the early 1980s. I'm still researching this one.

Unless subtantiated by fire test data, return the plans to the submitter.

Looking at the Tyco data sheet, this is a Special sprinkler. For example, if rack storage is introduced the sprinkler's spacing is limited to 10-0. I would confirm the spacing in relation to the method used to facilitate storage. Also, make sure the hydraulic calculation method matches the minimum number of sprinklers and minimum discharge pressures specified by Tyco and NFPA 13.

RE: shelve storage 16 feet high

(OP)
thanks for the responses.

Waiting for about the third request for more design criteria from the consultant.


http://tyco-fireproducts.com/TD_TFP/TFP/TFP332_01_2005.pdf

if you look at the 2nd page of tyco data sheet it appears that there are some set ups for storage above 15 feet.

If they design to a higher standard say rack storage to 20 feet, same class commodity, would you say that should meet the demand of shelve storage to 16 feet???

RE: shelve storage 16 feet high

Stookey:

Where did you get the 10' max spacing on the head.  I didn't see it in the data sheet.  I know that NFPA 13 allows up to 12' (12'6 in a 25' bay) for storage.  I hope I am not missing something as I have seen jobs with these heads at 12' x 8' spacing.

cdafd:

I would stick with 15' being the max allowed for shelf storage without full scale fire testing.  That is the limit imposed by 13 and I don't think this data sheet clearly specifies that the criteria is for shelf storage in excess of 15'.  It is talking about rack and piled storage being higher, but not shelf.  A quick call to Tyco may clear that up.

Good luck!

T

RE: shelve storage 16 feet high

(OP)
A quick call to Tyco may clear that up.


that was my next step

will give up for today and fight another day

RE: shelve storage 16 feet high

Travis:

See this data sheet.

http://www.tyco-fire.com/TD_TFP/TFP/TFP330_03_2006.pdf

This confirms our previous conversation that one literally needs to reference the SIN when discussing the design limits of sprinklers.

The suttle differences in the name of sprinklers can really cause confustion.

And I agree, I see nothing in CDAs data sheet that allows the height of storage to exceed 15 feet.

RE: shelve storage 16 feet high

(OP)
so even though the data sheet under "Design Criteria" talks about "rack storage" "up to 25 feet high" you all are saying that would not apply to shelve storage to 16 feet???

are you saying the shelve storage to 16 feet is  more demanding than rack storage to 25 feet???

RE: shelve storage 16 feet high

I am saying that the heads have not been tested for shelf storage in excess of 15'.  I don't really have any idea of which is more demanding.  Does the EC25 allow for shelf storage in excess of 15'?

RE: shelve storage 16 feet high

Who is "they" that is specifiying those sprinklers?  Have you called "them" to ask how and why they chose those heads?  Also, check with AHJ.  

RE: shelve storage 16 feet high

CDA

A shelf is different than a rack. First, the depth of a rack is not limited. A shelf's depth is limited to 30 inches. Secondly, a shelf is allowed to have solid tiers. Third, a shelf has no flue space. See the definition of a shelf in NFPA 13 and Annex A.

So basically you have a mechanism that can have multiple tiers with a limited depth and no flue spaces. When ignition occurs, one must assume that that the entire array can become involved because the sprinklers will only be pre-wetting exposure shelves because of the solid shelves and no flue spaces to allow water penetration.

Travis, nothing in the Tyco EC-25 data sheet permits its use for shelf storage > 15-0 AFF.

RE: shelve storage 16 feet high

(OP)
HELP

new design
elo head
http://www.tyco-fire.com/TD_TFP/TFP/TFP342_03_2007.pdf

still trying to protect shelves to 16' 6"

proposal that I do not understand is

two design areas in side by side in the retail area.
area 1 .49/2000 reference chapter 12 and still using rack storage design criteria 12.3.2 2002
head spacing 91 sq ft

area 2 .6 / 900 reference 2304.2 ifc 2003
head spacing 80 sq ft this was for group a plastic limited amount

What's up????
1. after posting will call tyco
2. design submitted by a consulatant, so can it be considered perforamcne based design??????
3. now understand the difference bewteen trying to protect shelves verses racks.
4. any other help/ questions
5. seek third party opinion in design using 104.7.2?????

RE: shelve storage 16 feet high

Ok..I think I have it sort of figured out.  They are using the wrong head.  It is required to use EC-25.

12.7.2.6  A wet pipe system designed to meet two separate design points — 0.49 gpm/ft2density over 2000 ft2 and 0.55 gpm/ft2 density for the four hydraulically most demanding sprinklers — shall be permitted without the use of in-rack sprinklers in retail solid shelved steel rack structure when the following are met:  
(1)     An extended coverage sprinkler with a nominal K-factor of 25.2 listed for storage occupancies shall be provided.
(2)     Storage height shall not exceed 16.5 ft.
(3)     Ceiling height shall not exceed 22 ft.
(4)     Shelving structure shall not exceed 51 in. aggregate depth or 148 in. in height.
(5)     The intersection of perpendicular steel racks shall be permissible as long as no storage is placed within the void space at the junction of the racks.
(6)     The top shelf shall be wire mesh.
(7)     A minimum aisle width of 4 ft shall be maintained between shelf units and other displays.

His criteria is still slightly off, but this may be where he is getting some of the information.

RE: shelve storage 16 feet high

(OP)
TravisMack

the only sections cited are for the desgin of the system

12.3.2.1
12.3.2.1.2
table 12.3.2.1.2 class IV over 12 ft no in racks, and fiqure 12.3.2.1.2(d)  (curve g)                       (apply fiqure 12.3.2.1.5.1-yes)

figure 12.3.2.1.5.3 70% for 16.6 high storage

12.3.2.1.5.9



how do you feel about the comments that a shelve fire may be more demanding/ or different developing fire than a rack, so the heads may not activate as fast and water may not get where it needs to go as easy??

thanks for the help.

RE: shelve storage 16 feet high

12.3.2.1.2 is for NO SOLID SHELVES.  You have shelf storage, which if I understand correctly is a solid shelf.  As such, it doesn't apply.

I don't know who the consultant is that came up with this, but I still stand by my original assumption that they are wrong, or need to provide full scale fire testing.  Otherwise, make the top shelf mesh and change to EC-25 sprinklers.

People make mistakes.  Unfortunately, it is not uncommon.  I do it all of the time smile  

Whoever put forth this criteria on shelf storage to 16.5 feet simply selected the wrong criteria and the wrong head.  You said they went with the 0.49 density.  That comes straight from the section I posted above.  I would just put it back on the "engineer of record" to show how it is compliant.  If you need rationale, quote him the definitions of shelf and solid shelves per 13.  Then show him the section I quoted above.

It means they will have to redesign the system, but it happens some times.  It is not fun, but we have all gone through it.

So, I can't really say that a shelf fire will develop differently and/or be more demanding.  But, I can say that NFPA 13 has distinctly different criteria for shelf vs. rack storage.  It is pretty clearly spelled out what they need to do for shelf storage in a retail setting.  They just need to follow 12.7.2.6.  Nothing more or less without full scale fire testing.

I think the consultant may be digging their heels in trying to save face for a simple mistake.  With all of the changes in fire sprinkler technology, it is very easy to make a mistake like this.  Thankfully, you caught it in the early stages and it can be corrected.  It is better to be caught now, instead of having 200k sq ft of piping up in the air.

Good luck!

Travis

RE: shelve storage 16 feet high

(OP)
TravisMack

thank you for your insight.

I am trying to stay away from telling them to follow a certain section, because I do not want my name on the design.

This is a big box retail store and they have a set design that they expect the ahj to accept.


we have been beating this around for about three months and now the building is actualy going up so they are getting a little more serious.

I still need to talk to tyco about the ELO head to see if they offer any help, but seems like I need to send it back one more time to see what they do.

RE: shelve storage 16 feet high

Good analysis Travis. I see many man lifts at night with lots of plastic sheeting covering up the racks on this job as the sprinklers are being changed.

RE: shelve storage 16 feet high

You don't need to to offer the section.  I have been involved with this type of scenario on more times than I like (contract drawings being wrong, but owner / GC expects them to be approved).  If you have a good relationship with the AHJ, talk to him first.  He is the one with the big hammer.  Let him tell the consultant that they are wrong.  

If you have any reviewing input or anything like that, simply state that NFPA 13 states shelf storage shall not exceed 15'.    However, there are special criteria in 13 that may account for this situation.  Make them go look for it.  The funny thing is that if you look at the White Paper that Tyco put out on EC25 sprinklers, it talks about Bed Bath & Beyond and like stores for the same scenario that I posted above that was incorporated into 13.  So, this arrangement has already been deemed appropriate for these types of retail stores.

You are going to come out the hero if you let them know now that the design is wrong and needs to be fixed.  If it gets installed like you have described, it will be wrong.  If some one later on is smart enough to catch it, it will require a lot of re-work.  The EC25 has a 1" thread so all of the existing outlets would have to be plugged and new outlets drilled.

Worst case scenario would be for a fire to occur and the system not be able to contain the fire.  Then, the industry has to deal with the bad press associated with a failed system.

I know you are in a very awkward position.  However, you at least have the opportunity to save the owner a lot of money and potentially save the life of people in the store should a fire occur.

Good luck in your decision as to how to proceed.  I don't envy your position at all.

RE: shelve storage 16 feet high

(OP)
TravisMack

I R the AHJ

still need a little time to digest the info and look at 13 and the ec25.

any further thoughts will be welcomed

stookey any thoughts on the ec25 used for the shelve protection??

RE: shelve storage 16 feet high

CDAFD:

Ok, you are in the awkward position.  Again, I will state that it is better to question it all at this time instead of waiting until it is up in the air.

Like I said, people make mistakes.  It is just part of life.  Heck, I may be totally wrong on what I have stated on this subject.  It won't hurt my feelings, and it won't be the first or last time I was wrong.

I understand not wanting to rock the boat.  I am going to assume the consultant for this box retailer was a Schirmer, Rolf Jensen or TVA type company.  I have done a lot of work with all 3 of them.  They ones I have dealt with have been very receptive when I point out something during the shop drawing phase.  Sometimes, they are able to provide a solid justification for what they did.  Other times, they simply admit it was wrong and work to have the design fixed.

I would rather see the design changed now instead of reading a news headline: "3 people dead.  Fire Sprinkler System FAILED"

Again, good luck!  I don't envy your position.

RE: shelve storage 16 feet high

(OP)
I like to rock the boat when it needs to be rocked.

I wish it was one of the name brand consultants, but it is not. I would feel a little better if it was.

I keep forgetting to ask if FM has any data sheets for shelve storage?????

RE: shelve storage 16 feet high

(OP)
TravisMack

Do you happen to have a 2002 nfpa 13 handbook, if so look at page 466
The commentary in blue. it refers to 12.3 if there is shelve storage over 15 feet. I know that this is commentary only, but also look at a A.12.2.2.1.1(3)

RE: shelve storage 16 feet high

CDA:

Ok, I see where you are at.  But, I think if you go to 12.3 then you are going to need to look at criteria for SOLID shelves.  All of the stuff in 13 refers to not having solid shelves.  You basically need to add in-rack sprinklers at every level is there is solid shelves, unless you meet some very specific criteria such as less than 20 sq ft (I believe, going from memory here) and some strict criteria on flue spaces.

If they meet all of the criteria about shelves such as:

12.3.1.9 Solid Shelving.
12.3.1.9.1  Where solid shelving in single-, double-, and multiple-row racks exceeds 20 ft2 but does not exceed 64 ft2 in area, sprinklers shall not be required below every shelf, but shall be installed at the ceiling and below shelves at intermediate levels not more than 6 ft (2 m) apart vertically. (See Section  C.11.)

12.3.1.9.2  Where solid shelving in single-, double-, and multiple-row racks exceeds 64 ft2 in area or where the levels of storage exceed 6 ft (2 m), sprinklers shall be installed at the ceiling and below each level of shelving.

The problem is the table they chose says no solid shelves:

Table 12.3.2.1.2  Single- or Double-Row Racks — Storage Height Up to and Including 25 ft (7.6 m) Without Solid Shelves

This is where NFPA 13 gets confusing.  They mention what you can do for solid shelves, but do not provide any criteria that I have found for solid shelf densities.  What I have done in the past is calculate the overhead at 0.3/2000 and then figure 7 heads on each of 2 levels at 30 gpm.  I had this backed up by a local FM guy on a specific project.  It was the best we could come up with for the existing arrangement.  

However, based on what I think you have been provided, they are looking for no in-rack sprinklers and some obscure density.

So, back to the point.  Either the shelves are <20 sq ft and they can be considered open shelves.  Or they go to EC25 sprinklers and meet the criteria specified in NFPA 13.

I hope Stookey gets a chance to chime in here.  He may have some other advice to offer based on his past experience in storage facilities.

Travis

RE: shelve storage 16 feet high

(OP)
I did a Target storeroom and they had the shelves with solid shelves, I think they used the ec 25 head on that with no in racks, will have to go back and look at hose plans.

They actually did some fire testing to support thier design.

Will look at 12.3 and solid shelve issue

RE: shelve storage 16 feet high

Of those that I am aware, Target, Sam's & WalMart all specify EC25 in their stores.  Their specs all come straight from 13 or the EC25 white paper which is the same thing.

I believe that Lowe's has done some fire testing for their paint storage racks in the customer paint dept.  Other than that, I am not aware of any fire testing for the major big box retailers.

Which store chain is this, if you don't mind my asking?

Travis

RE: shelve storage 16 feet high

(OP)
TravisMack

would prefer at this time to say it to you in private

RE: shelve storage 16 feet high

no problem. I understand!

Travis

RE: shelve storage 16 feet high

CDAFD:
So what has been the final outcome on this project?  Did it get accepted as is, or did it have to go back for redesign?

Travis

RE: shelve storage 16 feet high

(OP)
TravisMack

I really have not had time to think it through, but have skimed it.

I am going to try to set down right now and read through chap 12, but I think I need to send it back one more time and have them address the issue between thier design for racks with no solid shelves and the shelves they want to install with soild shelves at each level.


So long story it will go back one more time.

do you post any on the ICC site, and if so by what name???

http://www.iccsafe.org/cgi-bin/ultimatebb.cgi

RE: shelve storage 16 feet high

CDA:

I have never used that site.  I signed up and am awaiting "acceptance."  I have put in the same user name: travismack

Travis

RE: shelve storage 16 feet high

(OP)
I am slowly going through 12.3

shelves are 25 1/2 inches deep and 48 inches long

RE: shelve storage 16 feet high

As long as they maintain the proper spacing between the shelves..I think it is around 4" at the "flue" spaces, shelves of those dimensions would qualify as open.

At least that is what I remember going from memory.

T

RE: shelve storage 16 feet high

(OP)
well they are doing some 25 1/2 back to back shelves and about 20 feet run, which I read to throw them into solid shelve issue.
told them Table 12.3.2.1.2 NFPA 13 2002 applies to racks with out solid shelves

so either provide fire testing for design proposed or submit another design for solid shelves up to 16.5 ft.

RE: shelve storage 16 feet high

GREAT CALL!

It is never fun to have your design thrown back at you, but I would always prefer to modify a design vs sitting on a witness stand explaining why someone's loved one died in a fire due to a poor system design not meeting the minimum standards put forth by NFPA 13.

Again, good job!

RE: shelve storage 16 feet high

(OP)
New Wrinkle

Looking at all the documentation

1. shelves are only 12 ft to the top

2. They store on top of the top shelve 4 1/2 feet

Not sure how or if that matters

RE: shelve storage 16 feet high

So u have 16.6' of storage, not 12' storage!

RE: shelve storage 16 feet high

(OP)
LCREP

Yes, But

The top of the shelving unit only goes to 12 feet.

There will be storage on top of that to 16.5 feet

nfpa 13 design can handle 15 feet shelving units.

so how does the 12 foot shelve units with 4 1/2 on top of that jive with nfpa 13

can the shelve design criteria be used since the shelves are under 15 feet????

RE: shelve storage 16 feet high

CDA:

No, you have to go with the TOP of storage.  Let's say that I have a rack that stops at 20' aff, but my product is in 10' tall crates.  If I store that product on the top tier, then I have 30' storage.

You always have to go with the top of storage, not top of storage structure.

Another way to think of it:  Would you allow ESFR sprinkler deflectors at 30' and storage to 29'6", even if the top tier of the storage structre was only 25'?

Good luck with your project there.

Travis

RE: shelve storage 16 feet high

As Mack said on the height.

The height of storage is always measured from the floor to the highest box. When I inspect warehouses I always bring a tape measure ( 30' Fat Max by Stanley) and a laser tape measure (about $100, mfg by Stanley). The laser tape measure is critical for ESFR and and plastic pallet and rack storage. You have to measure roof height and distance from height of stock to the roof. The greater the distance, from the roof to stock, the worst condition it is with plastics. Aisles, rack width, etc also play critical roll in determine if the fire protection is adequate.

RE: shelve storage 16 feet high

(OP)
I understand that I have 16.5 feet of storage, and they have to design to that.

BUT!!!

What about the shelves that only go to 12 feet??? would that help them in 13 covers up to 15 feet of shelves??? do not have 13 in front of me, and will have to research it a little more.

RE: shelve storage 16 feet high

CD,

IF they can limit the storage height to 15' then yes it works. BUT how will they do this?? Unless you visit on a regular bases to enforce the height, the second they get a shipment in and need to put it somewhere it will go to the 16.5". Just bounce the plans and let them worry about it.

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