Last week, we reviewed the dangers idle pallets can pose to warehouses and distribution centers. As we mentioned, it is critical to recognize the fire hazards that idle pallets pose, and fully evaluate the idle pallet storage location and arrangement to determine the sprinkler protection needed. This week, we will review the protection requirements for idle pallet storage in both NFPA and Factory Mutual (FM).

NFPA 13 (2016 Ed) Section 12.12 outlines NFPA’s recommended idle pallet storage locations and the protection required for various idle pallet storage arrangements.

FM Datasheet 8-24 Idle Pallet Storage (January 2013/Interim Revision January 2015) outlines FM Global’s recommended idle pallet storage locations and the protection required for various idle pallet storage arrangements.

Storage Locations

Per NFPA 13, potential storage locations for idle pallets, (in order of preference) are as follows:

(1)    Stored outside

(2)    Stored in a detached structure

(3)    Stored indoors where arranged and protected in accordance with NFPA 13  12.12.1.2, 12.12.1.3, 12.12.2.2 & 12.12.2.3

Indoor storage can be further divided into the following categories (in order of preference):

(1.)  Attached building- Building that has a common wall with the main warehouse building

(2.)  Cut-off room- Room located within main warehouse building, but having at least one outside wall

(3.)  Inside cut-off room- Room located in the main warehouse building with no exterior wall

(4.)  Open storage within main warehouse- Open storage of idle pallets within the main warehouse

Sprinkler Protection- NFPA

When idle wood pallets are stored outdoors, NFPA 13 Table A 12.12.1.1 (b) provides the minimum separation distance required from the building to storage of idle pallets depending on the construction of the exterior wall and the number of idle pallets to be stored outside.

When idle wood pallets are stored indoors, NFPA 13 requires sprinkler protection to meet the minimum requirements outlined in:

Table 12.12.1.2 (a) – Control mode density/area sprinkler protection of Wood Pallets

Table 12.12.1.2 (b) – CMSA sprinkler protection of Wood Pallets

Table 12.12.1.2 (c) – ESFR sprinkler protection of Wood Pallets

When idle plastic pallets are stored indoors, NFPA 13 requires sprinkler protection to meet the requirements outlined in:

Section 12.12.2.2.4.1 (1-5) where idle plastic pallets are stored in a cut-off room

Section 12.12.2.2.4.2 (1-4) where idle plastic pallets are stored without cut offs

Section 12.12.2.2.4.3 (1-4) where idle plastic pallets are 4 feet or less

Table 12.12.2.2.3- ESFR sprinkler protection of Plastic Pallets

The tables and sections listed above provide information on the required sprinkler design (density/area, k-factor, # of heads, and minimum operating pressure) based on the maximum storage height,  maximum ceiling/roof height, sprinkler orientation, type of sprinkler system (wet/dry), temperature of sprinkler, and storage type (rack/on floor). These tables and sections also provide guidance on the required rating of walls and steel column protection needed, where applicable, as well as the separation distance required between piles of idle pallets.

Sprinkler Protection- FM Global

 Per FM DS 8-24, outdoor storage of idle pallets is the preferred storage location followed by indoor storage with appropriate sprinkler protection provided as outlined in FM DS 8-24.

When idle pallets are stored outdoors, FM DS 8-24 Table 1 provides the minimum separation distance required from the building to idle pallet storage, depending on the construction and fire rating of the exterior wall and the number of idle pallets to be stored outside. FM DS 8-24 Table 2 provides the minimum separation distance required between piles of idle pallets stored outdoors.

When idle wood pallets are stored indoors, FM DS 8-24 requires sprinkler protection to meet the minimum requirements outlined in:

FM DS 8-24- Table 3 and Section 2.2.3 for wood pallets stored on the floor and in racks.

When idle plastic pallets are stored indoors, FM DS 8-24 requires sprinkler protection to meet the requirements outlined in:

FM DS 8-24- Section 2.2.2 for plastic pallets stored on the floor and in racks.

The tables and sections listed above provide information on the required sprinkler design (k-factor, # of heads, and minimum operating pressure based on the maximum storage height),  maximum ceiling/roof height, sprinkler orientation, type of sprinkler system (wet/dry), temperature of sprinkler, and storage type (rack/on floor). These tables and sections also provide guidance on the required hose allowance and the need for horizontal barriers in the racks, where applicable.

Idle pallets really do present a high-challenge fire hazard in warehouses and distribution centers. Being aware of the hazard they pose, and fully evaluating the location and arrangement of idle pallets to determine the sprinkler protection needed, will help reduce the potential for a catastrophic fire loss originating from the storage of idle pallets.

 Check out this raw video of a pallet yard fire earlier this year: