Racking accidents do happen sometimes. To reduce the risk of racking accidents, it is helpful to be aware of some of the likely causes of these accidents. Each year, accidents occur on account of handling loads stored on pallet racks. This article discusses some of the causes so that steps can be taken to reduce the risk of racking accidents.
Risks related to the use of pallet racks are many. For example, there is the risk of total or partial collapse. There is also the risk of falling loads. Then, there is risk of personnel falling from various heights while handling loads. And, there are other risks as well.
Total or partial collapse of a pallet racking system can occur if, for example, the configuration of the original rack installation is modified in a way that significantly changes the rated load capacity of the racking.
For instance, some of the beams might have been removed. Typically, what is encountered is a situation where beams nearest to the floor are removed in order to accommodate taller loads.
This modification might result in a configuration with the first beam level at 96” from the floor, or even higher. Whenever there is a change in rack configuration, a Pre-Start Health and Safety Review of the racking is required by health and safety regulation in Ontario.
Another situation that could cause total or partial collapse of a pallet racking system is overloading. In this scenario, loads placed on the racks exceed the rated load capacity. This can happen in two ways. One is general overloading throughout the storage system, and the other is a more localized overloading that can cause collapse.
A third likely cause of racking collapse is impact. In a storage and handling environment, impact is typically caused by forklift trucks. Depending on the type of racking components used and the rack configuration, there might be some resistance to collapse from forklift impact.
For example, if the racks are Back-to-Back or Double-Deep, and they are well constructed, there would be greater ability of the racks to resist collapse from forklift impact than single rows of selective racking. Should a forklift accidently impact a single row of pallet racking that is not anchored to the concrete floor, and not cross-aisle tied, the risk of collapse might be relatively high.
One of the less recognized risks of total or partial collapse of pallet racking is inadequate repair of original rack components. Racking components, such as upright frames, which have been repaired, might seem normal to personnel working in a manufacturing or warehouse environment.
However, improper repair, while difficult to detect at times, is cause for concern. For instance, a common occurrence is damage caused by forklifts impacting the front posts of upright frames. If repair is done by replacing a section of the front post, the repair should be accompanied by a document, signed and sealed by a professional engineer, indicating that the repaired components meet or exceed the rated load capacities of the original equipment.
As an aside, here is something else to consider. Should modifications be made to racking components, does the liability still rest with the manufacturer of the original equipment? It seems reasonable to suggest that, once components have been modified, the company that modified the racking components becomes responsible for the rated capacities of the modified equipment.
There are other factors, which can cause total or partial collapse of pallet racking. The risks noted above are the more common ones to be mindful of.
Apart from total or partial collapse, there are accidents, which might occur on account of falling loads. For example, there might be pallets, which are in very poor condition, and failure of pallets to support loads placed upon them can cause pallet material and products to fall. Remedying this situation requires someone to identify pallets, which are in poor condition, and replace them.
In addition, there is risk of falling loads that might occur due to improper packing. For example, where there is a lack of cohesion of materials stored on pallets, there is risk that materials might fall.
Another scenario, which is sometimes encountered, is improper positioning of pallet loads on beam levels. For example, a pallet load might be positioned so that most of the overhang is at the front of the rack and, as a result, the far edge of the pallet is barely resting on the back beam. Impact of the racks by forklift could result in the pallet load falling from the rack. In this type of situation, the use of safety bars or wire decks helps to alleviate the risk.
Yet another risk of falling loads lies in the unhooking of beams. This occurs when a forklift is used to lift a pallet load from one beam level, and the top of the load makes contact with beam(s) above. In the process, the beam(s) above can become disengaged from the upright frames, resulting in falling loads. While the use of safety pins helps in this regard, bolting beams to upright frames might be better.
Apart from falling loads, there is risk in some operations of personnel falling from heights. These accidents can occur on account of one or more of the following risk factors: The material handling equipment is not suitable for lifting personnel, or there is no means of protection such as guardrails, or safety harnesses are not used by personnel.
Wherever racking is used for storage, there is risk of racking accidents occurring. Being aware of some of the risks can only help when taking steps to reduce the risk of racking accidents.
Jack Jagernauth, P.Eng. is a project engineer with Rack Inspections Ontario, an engineering company providing services related to racking safety, racking inspections and PSRs. He may be reached at 905-847-3640 or jack@rackinspectionsontario.ca, or through the company website: www.rackinspectionsontario.ca.