Understand the capacity of wire mesh pallet rack decking.
A year ago, the Rack Manufacturers Institute (RMI) elected to allow manufacturers of wire mesh decking to be members. The basis was straightforward enough: Pallet rack and decking are an integrated weight-bearing system.
Decking can, and often does, directly bear the total weight of the application’s load and transfers that load to the beams of the pallet rack. Regardless of the weight-bearing capacity of the rack’s beams, an improperly overrated deck can and will jeopardize the load-bearing capacity of the entire system and result in a failure.
The members of RMI recognized that they and the material handling industry would be well served by welcoming the decking manufacturers into their tent and, in turn, including them under their influence.
Deck Capacity Rating
Just as there is an ANSI standard for determining the load-bearing capacity of selective pallet rack, so is there an ANSI standard for pallet rack decking. It is MH26.2 and has been a published standard for more than a decade.
MH26.2 describes step-by-step the two weight-bearing tests that determine the rated capacity of a deck. Specifications for the testing apparatus itself are detailed in MH26.2. There is no other ANSI approved method of rating a deck’s capacity. Before the end of the year, MH26.2 will be the basis by which RMI will certify with an R-Mark a given load table for decking when that deck manufacturer can prove their strict conformance to MH26.2.
Only in the last couple years has MH26.2 begun to serve its intended purpose—that is, to bring an objective and professional industrial discipline to a material handling product that, when misused and/or misrepresented, can result in a deadly accident.
Where’s the Liability?
Simply put, few material handling distributors and even fewer end-users are at all conversant on the specifics of properly rating the capacity of a deck. That is not criticism of either group. Why should a distributor today know what constitutes an acceptable ANSI/MH26.2 product in terms of material content and capacity? We, the manufacturers, have taken far too long to catch up with the rack manufacturers, who some five-plus years ago instituted R-Mark for selective rack.
We, the deck manufacturers, are first and foremost the bearers of the original liability.
Webster’s Collegiate Dictionary defines “liable” as the probability or possibility, because of one’s position, of being responsible to others, and that you are obligated to be responsible whether you choose or choose not to honor and own up to that responsibility.
A deck manufacturer “discharges” this liability for being responsible by first implementing MH26.2, then strictly adhering to it when publishing and claiming capacity ratings, and by going “overboard” to educate and inform both distributors and end-users of rack decking to MH26.2. This is the state of the industry today! We, the deck manufacturers, are nearly there in getting our act together so we can go forward with R-Mark certification. And it is about time that we are!
Liability does not stop with the manufacturer. The material handling distributor’s liability is their responsibility to choose to become more knowledgeable and then to become more attentive to the rating claims made by each manufacturer. By doing so, the distributor protects his or her own interests and does a better job of representing the safety interests of the customer, the end-user. The distributor’s position in the supply channel obligates them to this liability. Discharging the distributor’s responsibilities will become easier as the R-Mark certification by manufacturers takes effect.
At present, sound business judgment, good common sense and comparing quoted claims are the tools available to the distributor. Wire deck manufacturers utilize a common family of gauges of channel steel and wire. The laws of physics and metallurgy determine the capacity of a given deck. Decks made with a different number of channels and differing gauges of steel do not have the same rated capacity. The end-user truly gets what he pays for when he buys a deck.
So What’s the Rub?
In today’s economy, price alone can often be the key factor in securing a sale. What better way to reduce the cost of a deck than by eliminating a portion of the material cost by reducing the gauge of the material and/or the number of channels? But then is the deck manufacturer, and secondly the distributor, as equally willing to acknowledge and then provide the reduced rated capacity that goes hand-in-hand with a lighter weight deck? It is common knowledge that MH26.2 includes a two-times (2X) safety factor before structural collapse. Unfortunately for some, this is more than ample comfort to knowingly overstate a deck’s capacity.
Since today the manufacturer is, and tomorrow the distributor will be, in a position of knowledge and “knowing better,” each discharges his liability by responsibly disclosing and informing the end-user of the correct facts regarding the rated capacities of pallet rack decks.
Most deck manufacturers are responsible and seek to properly substantiate their claims of rated capacities. Before the end of the year, distributors will be able to distinguish among manufacturers based upon RMI’s R-Mark certification. The discipline of MH26.2, coupled with the professionalism of responsible distributors representing the interests of end-users, will quickly result in a much-improved material handling industry.
|Meet the Author
Craig F. Chamberlin is president/CEO of AWP Industries, located in Frankfort, Kentucky, and on the Web at www.awpind.com.