what is the minuminm density requirement for an existing warehouse (retail packaging)

[doingwhat]

- building height is about 17 ft
- storage height is less than 12 ft

The warehouse will be used to store/retail packaging for sunglasses. Is this belong to ordinary hazard group 2 (Mercantile? )

 

[LCREP]

Need more info on the storage configuration is it racks, shelves, pallets, but any of these will not be adequate as most sunglasses are made out of group A plastic. If plastics max height would be 5' as per 13 with ord haz Grp 2 system, again as per 13.

 

[doingwhat]

i think sunglasses packaging is treated as Class IV commodities according to NFPA figure 15.2.2

Note: cartons that contain group a plastic materal are permitted to be tread as class IV commodities under the following conditions.
1) There are multiple layers of corrugation or equivalent outer material that would significantly delay fire involvement of the group a plastic.
2) The amount and arrangement of group a plastic material within an ordinary carton would not be expected to significantly increase the fire hazard.

13.2.1
Table 13.2.1 and figure 13.2.1 shall apply to any of the following situations:
2) Miscellaneous storage of group A plastics up to 12 ft in height

Table 13.2.1 Palletized , storage height >10 to <=12, design curve = OH2

Btw, is there any table in nfpa to determine sunglasses is belong to group A plastic?

 

[stookeyfpe]

I don't know where your project is at but if it's in the US and the jurisdiction has adopted the 2012 International Fire Code, you may have the option of reducing the classification to Class IV by applying Figure 3203.7.4 (it's Section 2303.7.4 in the 2009 and earlier editions). You will need to essentially weigh the finished package and evaluate the plastics used in the manufacturing of the product as well as any plastics used in packaging.

 

[LCREP]

So what kind of sunglass do we have, metal frames and glass lenses, metal frame with plastic lenses, all plastic both frame and lenses, cheap Walmart type or expensive $200 pair? This will all drive the final commodity. BUT how sure are you they all are class IV, how many pallet loads can be group A plastic before it becomes a problem? Well take a look at what NFPA 13 says about this below for mixed commodities.

As you can see below 10 pallet loads of a higher commodity is permitted in a 40,000 sq.ft. warehouse. That is NOT a lot, it also says they can not be near each other. It does not take much for the fire to take hold if the design is not correct. Based on full scale testing they found it only takes a single pallet load in a fire to overcome the sprinkler density and not control a fire.

So why did I go with Group A Plastic because I have been down this road way too many times. Products change and sprinkler designs do not. I work for an insurance company with a large engineering staff. We find about 50% of the warehouses we evaluate the sprinkler design is not correct. So that is why I said Grp A.

Remember the answer is not as simple as what the code says, sometimes you have to use judgement and experience. Many new warehouses have gone to ESFR sprinklers with the hope it would solve all problems with commodity classification and inadequate sprinkler protection. Unfortunately ESFR has it's own problems and is not a one size fits all approach.


5.6.1.2 Mixed Commodities.
5.6.1.2.1 Protection requirements shall not be based on the
overall commodity mix in a fire area.
5.6.1.2.2 Unless the requirements of 5.6.1.2.3 or 5.6.1.2.4 are met, mixed commodity storage shall be protected by the requirements for the highest classified commodity and storage arrangement.
5.6.1.2.3 The protection requirements for the lower commodity class shall be permitted to be utilized where all of the following are met:
(1) Up to 10 pallet loads of a higher hazard commodity, as described in 5.6.3 and 5.6.4, shall be permitted to be present in an area not exceeding 40,000 ft2 (3716 m2).
(2) The higher hazard commodity shall be randomly dis- persed with no adjacent loads in any direction (including diagonally).
(3) Where the ceiling protection is based on Class I or Class II commodities, the allowable number of pallet loads for Class IV or Group A plastics shall be reduced to five.

 

[stookeyfpe]

Unfortunately ESFR has it's own problems and is not a one size fits all approach.

Amen brother.

 

[doingwhat]

Even though the commodities is Plastic A, if the sunglasses is cartoned and place on a rack, the require density is still 0.20/1500 (Table 13.2.1)w/storage height between >10 to <=12

 

[stookeyfpe]

That's not what my Table 13.2.1 prescribes. You may design to an OH2 ceiling density but one level of in-rack sprinklers is also required.

 

[LCREP]

Doing

Based on the limited amount of details you have provided we have no idea what you have and if it can be protected with oh haz 2 system. Provide more details as follows:
1. The name of the plastic the lens are are made of. If more then one list all plastics. Use the list of plastics in NFPA 13 for the names.
2. Material the frame is made of, if plastic what type by name is the plastic.
3. You say consumer packaging, what is it, if plastic name of the plastic.
4. Provide details on the box they are stored in. On the bottom of the box is box mfg stamp, what does it say, how layers is the box certified as?
5. What type of rack, single, double,
6. How high is the stock measured from the floor to the highest box.
7. What is the distance from the top of stock to the roof.
8. What type of pallet is used, wood or plastic, if plastic provide details.
9. Any solid shelving on the racks, if so what is the sq. ft. of the shelve.
10. Are the flue spaces open or closed.

Answer these questions and we can help if that is what you want from us. Without these details we can not make a decision on what you have. If you have photos post them.

As I indicted in previous posts above providing an answer is more than reading a single section in 13 and having an answer. You need to look at everything and factor all of the info to come to a decision.