We have a customer who is building a storage building that includes flammable liquids.

The liquids are Class I-B flammable (as classified under NFPA 30).

I understand that there are limits for the quantity that is allowed within one control area. The Maximum Allowable Quantity (MAQ) is 120 gallons, from NFPA 30 tables. The reading can be increased 100% when a sprinkler system is used. 

So the limit increases to 240 gallons with sprinkler protection.

The number can increase even more when stored in approved liquid storage cabinets or safety cans, which I assume the customer would prefer.

So the final MAQ becomes 240 gallons x 2 = 480 gallons.

The biggest storage room is 2,000 square feet and the customer wants to exceed the MAQ to be above 480 gallons in that storage room.

I have understood that exceeding the MAQ is permitted if the building is classified as an H-3 Occupancy (High Hazard). This occupancy applies more restrictive requirements. 

Is there any numerical value for a new MAQ limit in that case?

My current path is as follows:
Class I-B liquid storage in Storage occupancy > maximum MAQ exceeded > building re-classified as H-3 Occupancy > but where is the new MAQ?

Thanks in advance for your input. I usually design under SFS and CEA standards, and they don't have the same MAQ concept within those standards.

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We have a situation where we'll have a piece of equipment in one control area that has a closed-use pipe arrangement with oxidizing gases that goes through different control areas. I've gotten conflicting feedback on this.

How do you figure the amount of "in-use" for each control area? 

Here's a sketch of the concept:

The equipment that is using the oxygen is on the fourth floor Control Area 2. The tanks that feed it are (2) 200 CF oxygen tanks that are in the second floor Control Area 1.

Which of the following two scenarios is the proper way to tally up the "in-use" quantity for the fourth floor Control Area 2 when comparing against the Maximum Allowable Quantities (MAQs)?

• Concept #1: The "in-use" amount is only the gas within the equipment itself, and only the gas within the piping to the extent of the control area wall.
• Concept #2: The "in-use" amount is all of the gas within the equipment itself, and all of the gas within all of the piping, and all of the gas within the (2) oxygen tanks which are actively hooked up to it.

 
My initial gut reaction was that the second option is correct, but now I’m not sure. My reasoning being that if there is an event in 4th floor control area 2 that causes a leak or something like that, it’s not going to just leak out what is physically within the control area… it’s going to leak out everything in all of the piping, all of the equipment, and all of the hooked up tanks. This is all presuming there are no safety devices to stop this from happening.

Assuming my initial gut reaction was correct, is there a way to limit the amount so that it stops at the control area wall?

As in: is there a safety device such as an automatic shutoff valve we can put at the wall such that in the event of a leak or other event, the automatic valve will shut off and then we only have to count the amount of gas between the equipment and the shutoff valve?

I’ve looked in the IBC and its commentary for more info, but couldn’t find anything helpful. I’ve also reached out to a number of different people and there seems to be a variety of different opinions on it.

Thanks in advance.

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We have a 300 sq ft control area (1 hour rated) for storage of Class IB flammable liquid. The 2018 IBC Table 307.1 permits 120 gallons (no sprinklers required), but this amount can be doubled if the building is equipped with an NFPA 13 automatic sprinkler system.

Our client would like to store about 165 gallons in the room (3 drums). The building is fully sprinklered.

What is the required sprinkler design density for this room?

We considered Ordinary Hazard Group 2 (same as lab area it supports) or Extra Hazard Group 2 (only occupancy in NFPA 13 that mentions flammable liquids).

If EH2, then the minimum water demand becomes quite large: 0.4 x 2500 + 500 gpm hose = 1500 gpm (Under the 2016 NFPA 13 - Section 23.4.4.2.5).

Could you help point us in the right direction? Thanks to all in advance for helping us hunt this down. 

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I wanted to pose the question on hazardous material storage lockers. We wish to protect the locker in accordance with Chapter 14 of NFPA 30 and have rated it for 4-hours to eliminate the need for fire separation distance to the immediately-adjacent main building as allowed.

The locker will not be structurally attached and will only have flashing connecting the two to keep out the elements, garbage, and animals. The locker will only have people in as necessary to get the liquids out.

The main building has a door on the "exterior wall" that opens and "reveals" the 3-hour rated hazardous material locker door, which you have to open to get inside the locker.

NFPA 30 2015 handbook Section 14.4.3 denotes that lockers over 1500 sqft should be protected permanent building such as attached buildings or warehouses. Our locker is under the 1500 sqft requirements so therefore I would say we are not a building but a "locker".

Therefore, the exterior wall openings allowances of IBC (2015) Table 705.8 would be to the lot line (over 10ft) and not the locker itself (0ft), allowing our client to access the locker from the inside of the main building and not having to go outside to access it from the exterior.

I was wondering if anyone has had a similar experience or if we should just call it part of the main building and protect it as such and lose the allowances of Chapter 14.

Thanks in advance!

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I have a customer that has a paint storage facility. All the liquids are Class III-B and stored at a maximum height of 6-ft with a minimum 8-ft aisle.

Does anyone have helpful information/guidance information for designing spill containment and coordinating ventilation requirements for a space like this?

I know containment is touched on in NFPA 30 - but I'm looking for some more in-depth guidance to get started. Thanks in advance.

We are trying to confirm sprinkler design criteria for a liquor company that has alcohol in boxes and on pallets.

The liquor is 100-proof alcohol. 

Trucks come in and unload in one area, where these are stacked one-high. Then, they are moved to another area and loaded on a different truck. They are not there for a long period of time.

NFPA 13-2013 calls this out as a Class IV for alcohol 100-proof or less. This project being under 12-foot high with high-temperature sprinklers, is the design criteria of 0.30 over 2,000 sqft acceptable?

The AHJ uses the 2019 edition of NFPA 13 and we can't find anything in there or in NFPA 30 that is similar, unless I'm missing something.

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We have a project that has Class III liquids in Non-metallic IBC (Intermediate Bulk Containers).

NFPA 30 Tables 16.5.2.9 and 16.5.2.10 list storage requirements for Class III liquids in Nonmetallic IBCs. Stacked IBCs are limited to two-high (~8 feet), and in racks, only single and double row racks are allowed.

Under Section 12.8, these containers may be protected as "high storage of Class IV commodities" through NFPA 13, provided that the volume is limited to 13,750 gal (Class IIIB).

Does this mean that under NFPA 13, IBCs can be stacked up to 40-feet with 45-feet ceilings as per Table 23.3.1, or in multiple-row racks up to 40-feet high with 45-feet ceilings as per Table 23.5.1?

Or similar configurations as per Chapter 22 (CMSA)?

Provided the volume limit is not exceeded, of course.

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NFPA 30 Figure 16.2.5 is used to determine if a material is viscous liquid or not.

I am having an issue with a interpretation of the "Weight (percent flammable or combustible liquid)".

Is this weight for the liquid only or the liquid plus the container?

Example: Total package / container weight = 2.48 grams. The liquid inside is a Class III-A mixture that is 0.78 grams (31.5%).

If I go with the entire package Figure 16.2.5 is applicable (less than 50%), but if I am just looking at percent of combustible liquids, all the liquid is combustible.

Thanks in advance. 

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I have a question regarding the need to provide electrical classification for a building using Class 1A flammable liquids.

For this building, 4 gallons could be out in use (located anywhere in the building). The MAQ is 10 gallons. I have discussed this with NFPA 30 committee, the manufacturer, and the AHJ (who is a knowledgeable FPE). They have all determined that even if the MAQ is not exceeded, electrical classification is required if a flammable/explosive mixture could be present.

The NFPA 30 staff directed me to a provision in NFPA 497, Section 5.5, that if the materials will not reach 25% of the lower flammable limit (LFL), this could be utilized to justify not providing classified electrical fixtures.

Does anyone know how to do this calculation, or know of firms that can be hired to do this?

I am an FPE and do not know how to perform it, and I have spoken with other FPE’s who also are not aware. The gentleman I spoke with at NFPA 30 agreed it would be by an industrial hygienist or a chemical engineer and not an FPE.

But does anyone know any that can be hired for a one-off calculation, or have a place where I could learn how to perform it myself (NFPA reference, SFPE article, course, etc.?).

Thank you!

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