FM Removes Class IV Commodies, Anyone Know Why?

[LCREP]

FM Data Sheet 8-1 Commodities Dated April 2014 as noted below, see section D, has a significant change. Anyone have any idea what is going on and will NFPA 13 also make this change? This will change many sprinkler designs going forward if FM or other insurance carries follow this change. FM now list 200 commodities, and provides guidance as to what the commodity is.

1.1 Changes
April 2014. The following changes were made:

C. Removed references to Group A, B, and C plastics. Plastics are now classified as unexpanded or expanded.
D. Removed commodity Class 4. Class 4 commodities are now treated and protected as cartoned unexpanded plastic (CUP).
E. Changed the classification of certain materials. This is due to changes in commodity classification (e.g., Class 4 to CUP), as well as recent testing conducted at FM Global.

 

[stookeyfpe]

I need to download and read the explanation. I do not understand why Class B and Class C were excluded. My experience is all US consumer electronic uses plastics modified by noble gases to reduce their flammability. It doesn't seem to matter if its a control board for a server or a flat screen TV. The manufacturers still remember the Mr. Coffee fires from the 1990s.

Part of me wonders if this is one testing lab versus another in the world of high piled combustible storage.

 

[Sdpaddler50]

My understanding is, Class IV was somewhat of a “fictitious commodity” to begin with. IE, fire lab tests early on were done for Class 1-3, and then plastics later, and the Class IV data was based on interpretations of those results.

I also think in our current plastic world that Class IV does not exist much. IE, except for say bicycles and a few odd commodities with limited plastics, items are either Class 1-3, or plastic.

I have called a warehouse IV in the past, only to find its plastic a year or two later. IE, plastics dominate in our products we use, and hence in warehouses.

The differences between A, B, and C are limited except when talking about plasticizers, PVC materials, and there are more exceptions.

This is a general response to what I think is going on.