Need help on NFPA 30 terminology

[INBCPE]

In NFPA 30, they talk about storage rack sections:

From the 1996 edition:
"4-4.4.4 Total quantity of liquids stored in a liquid warehouse shall not be restricted. However, the storage heights and maximum quantity per pile or rack section for unprotected storage shall comply with Table 4-4.4.1."

Can anybody please define a "rack section" for me? Is it a whole row, or is it one pair of uprights with tier beams? It makes a big difference. A row could be 150 feet long, where as a pair of uprights and some tier beams are typically only 8 or 9 feet long.

 

[stookeyfpe]

NFPA 30 has been extensively revised. Section 4-4.4.4 is now 4.4.4.4 in the 2000 edition. NFPA 30 does not establish a maximum rack length or a maximum number of racks. I've interpreted Section 4.4.4.4 to mean that the total quantity of liquids stored in each rack array shall not exceed the quantity limits based on the packaging size.

Since your in a liquid warehouse your quantity is not limited. However, because it is unprotected, your quantity limit in each rack is set forth in Table 4.4.4.1 for the class of liquid and its packaging.

I will also note that if this warehouse is being built in the US and the jurisdiction has adopted the 2003 International Fire Code (IFC), you cannot use the unprotected warehouse option based on the requirements in IFC Chapters 27 and 34.

 

[INBCPE]

What's a rack array? Could that be one rack array is one stand alone pair of uprights and 3 tiers? Or is a rack array 20 uprights all connected together with 3 tiers each? All of the pallet rack and material handling industry web sites define a "rack section" as two uprights with tier beams. So to them a row of racks with 4 uprights and tier beams is actually 3 "rack sections." Yet, I agree that it seems that NFPA is calling a rack section a whole row, because the quantities are pretty high. Example: the allowable unprotected quantity of 55 gallon drums of a Class II liquid appears to be 8250 gallons, or 8250/55 = 150 drums, or 150/4 = 37 pallets, or 37/2/3 = 6 bay sections if each bay section has 3 tiers. You couldn't fit that on one "rack section" if that rack section was only 2 uprights 3 tiers high.

Even if it means a whole row of uprights is one "rack section", I could double the allowable unprotected quantity by just taking the beams out from between the middle pair of a row of uprights. Essentially separating a single row into two rows.

Here's the back story:
I have a client I'm helping get out of a jam with the Fire Dept. He needs a new fire pump, and until he gets it, he'll be on city pressure. But the density isn't even enough for ordinary hazard, so it has to all be considered unprotected. We cut a deal with the city and county that in the interim we'll hire an off duty fireman to act as firewatch at night until the pump gets installed. But the fire chief and I both want to put together some good data on what's in the building, so as to help with future inspections and to act as a guide if it ever lights off. But he wants a "pre-pump" or unprotected list of allowable quantities, and a "post-pump" or protected list of allowable quantities.

 

[stookeyfpe]

Sorry for the delay in responding. NFPA 30 does not define a rack array. This means that you can use any rack type (single, double or multiple row) and any configuration of rack columns and beams so long as the height and quantity limits are not exceeded AND required dimensions between each rack are not exceeded.

For example, assume a liquid warehouse that is classified as unprotected that stores Class IC flammable liquids. The warehouse operator wants to store 27,500 gallons packaged in 50-60 gallon metal druums. In this case 10 racks, each limited to 2,750 gallons of Class IC flammable liquid could be installed. Neither the rack length, rack type, or arrangement between rack columns and beams are stipulated by NFPA 30. The only limit is quantity and storage height (5 feet).