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Minimum water supply required for NFPA 30 project

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SprinklerDesigner2

SprinklerDesigner2

Mechanical
Nov 30, 2006
1,244
So that you all know I feel I am not competent when it comes to NFPA #30 and I have hired an FPE to help with the design criteria for this project. That said I am not looking for any specific design criteria as I will probably be getting that on Friday or early next week.

What I am asking of those who do have some experience is does it look like we will have enough water given the following:

1. Water supply is 1,250 @ 100 psi fire pump from city connection. At churn we had 170 psi, 1,250 gpm @ 140 psi and 1,900 gpm @ 110 psi. Very flat curve and I recognize the 1,900 gpm is over the 150% but that is what I got.

2. Building is bent metal purlin 24'-0" eave and 31'-4" at peak.

3. Commodity stored on back to back racks without shelves sine three and some four tiers high. Looks like we can expect storage 20' high.

4. There is a list of 530 chemicals being stored and just a small representative sample is provided below:

30jpmqx.jpg


Looks like lots of required information is missing from that list but that is what I got and this is why I hired an experienced FPE to make sure I don't step in it.

From my amateur status going over NFPA #30 it appears the pump can't deliver enough water. I am not looking for any sort of definitive answer, like I said I will have that at the end of the week, but do you tend to agree with me from what your experience tells you?

Thanks.
 
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I am going from pure memory and it is fading as I get older. The last I did with NFPA 30 involved was a warehouse many years ago. I am thinking it was something like 0.3/5000. So, around 1500 gpm. If you have hydrants downstream of that pump, you may be in trouble.

However, I must qualify that this is just based off of a vague memory without going through archives to search for that project.

You may be able to look at using foam/water type systems and getting your water demand a bit lower. It is wise to bring in a qualified FPE on these types of projects.

Travis Mack
MFP Design, LLC
"Follow" us at
 
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You have insufficient information to come to a conclusion as to the required discharge density and design area. Under NFPA 30 you will need to know the container material of construction, if the containers are pressure relieving, and miscibility of the liquid. This appears to be automotive paint products.

The last major flammable liquid warehouse I did with IBCs and drum storage we ended up with a hydraulic demand of approximately 2,200 GPM. I don't see that with what you presented.

 
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Thank you Travis and Stookey for the input.

I didn't expect any design criteria and I suspected all along the criteria given was woefully inadequate. There is no way on earth I would go near a project like this without an FPE to cover my rear end. I would love to do the design work as long as he tells me the criteria to meet.... that makes it a fun project and not a nightmare.

While I would never use it the research I did indicated anything I attempted would exceed 2,000 gpm so there you go.

It's a rather large complex consisting of 10 buildings fed by a single fire pump with 9 hydrants downstream the fire pump. Everything is ESFR using K16.8 sprinklers @ 42 psi (peak does not exceed 32'-0" in any of the buildings. So yes, hose stream is added downstream the fire pump.

Did the acceptance test on the pump last week and it actually performed a little better than I had calculated with suction pressure about 8 psi more than what I calculated it would be giving me a "safety factor" of 24 to 28 psi depending on the building location.


 
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Don't be surprised to learn that ESFR sprinklers will not work for this hazard. NFPA 30 Table 16.5.2.8 does allow ESFR but only for very small volume metal packaging and generally it needs to be cartoned unless the containers are pressure-relieving style of construction. If your FPE can't figure out pressure relieving construction I think you have my e-mail address and if not, we'll find a way to communicate through the Oracle (that's Google).

In the representative sample spreadsheet I see some products that are probably Level 3 aerosols so you also have that to contend with. Your concern factor should elevate if the amount of aerosols exceeds 500 pounds because that's when the requirements in the International Fire Code will become applicable. You should also be aware that mixing of aerosols with flammable liquids has some very specific rules. Your client needs to know this.

If you have plastic packaging welcome to the world of NFPA 30 Scheme A or Scheme B.This will require horizontal barriers and in-rack or in-rack and face sprinklers. If the building is not built you may be able to take advantage of having the architect design a drainage system over a containment structure. Hopefully your FPE has worked through this.
 
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Stookey,

I am not surprised in the least as some on here have said, a countless number of times, some people think ESFR is the answer to everything when the truth is far from it.

When I wrote my proposal I made it very clear what commodities the sprinkler system would cover and what commodities wouldn't be covered.

Flammable liquid storage was first on the list of not covered items and along with flammable liquids I excluded rack storage with solid shelves or exposed expanded group A plastics.

The developer is super to work with they even let me have input as to placement of lights and even the steel. It was one of those jobs where I got to build my sprinkler and all the other trades built there work around me. This is a project I am proud of.
 
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Depending on the size of the containers and class of liquid, you may need to add AFfF foam if drainage is not adequate. Many folks forget to look at the required drainage in 30 which can add up $$ very quickly. Most of the protection is going with in-racks at each level and barriers at each level of storage. Do not forget to look at FM 7-29 for protection criteria, also NFPA 30 has a 2015 version, not sure if it has any additional protection over the prior year edition. NFPA did away with the line next to the new sections that have changed, which I hate!

 
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Just in case your FPE drives you to a foam system... It would be good if you ask for more criteria to be sure what is the best type of foam system for your case, use foam only if it is the only choice, some types of foam systems can be a pain in the a...
 
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Just a quick update.

Found out FM Global is involved and their account engineers will be telling me exactly what I need to do.

Great relief, the more I dug into it the less I wanted anything to do with the design specification of the project.
 
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I agree. Many don't like when FM is involved. I love it because they spell out exactly what they want for design criteria. Then, we just have to put the dots on the screen and connect them. It takes away a lot of headache on these complex projects.

Travis Mack
MFP Design, LLC
"Follow" us at
 
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Good to hear Travis. We try to spend a lot of time and dilligence at FM to get these projects right..the first time.
 
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So will you share the design they gave you?

 
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Stay with the information. FM has Confidential information sometimes that one may not find in the sheets.

R/
Matt
 
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Travis,

We agree on the FM jobs, they are always my favorite. Looking back over the years I've never had a "bad" FM job because they're so simple to do... connect the dots.

Have yet to receive the design criteria but from what I have heard it smells like a pre-primed foam system to me.
 
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Can you in-rack sprinklers, my guess you will see several levels, if not on each level......thanks for sharing on the foam.

 
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Right now the general concensus, by those not making the decision, is foam with rack sprinklers at every level.

I love the fact someone else making the design decisions.
 
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Once you stated FM, I figured it would be in-racks at every level. Possibly closely spaced and fairly high pressure. The foam may negate some of that. I would be interested in seeing the criteria when it is all said and done. I love jobs like these.

Travis Mack
MFP Design, LLC
"Follow" us at
 
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If it's storage of ignitable liquids, Data Sheet 7-29 will have most of the details. There is a free, public version of the doc. dispensing is covered in 7-32.

Also, One of the biggest differences between IFC/NFPA and FM is the max allowable quantity concept is not followed. A 55 gal drum of acetone will either burn abuilding down (if comb. Const.) or cause major smoke damage to a high value occupancy if it's not properly protected.



 
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