Our first question this month asks about altering racking and our second enquires about fitting racking near floor seams.
Can we alter our racking?
Q. I have been asked to make alterations (reinforcing) to a racking system by welding supports in positions.
I think it is to make partitions for storage which says to me that the incorrect racking system is being used.
At this present time I have refused to carry out said alterations as I don’t want to break any HSE rules or regulations.
A. The SEMA Code of Practice for the Use of Static Pallet Racking includes the following in clause 6.3 “Alterations”;
“The User shall not alter the rack configuration without reference to the Supplier or Manufacturer… Physical alterations to racking beams, such as welding additional bearers or cleats, etc., or a change of use from timber pallets to post pallets should not take place without the agreement of the Supplier of Manufacturer.”
BSEN15635 “Steel static storage systems – Application and maintenance of storage equipment” includes the following in clause 7 “Changes to the storage system” under item 7b. “additions or changes to the storage equipment by welding or bolting shall not be allowed unless specifically approved by the equipment supplier”.
Paragraph 634 of the HSE publication “Warehousing and storage – A guide to health and safety” HSG76 states that racking should never be altered without first contacting the manufacturer.
So, before carrying out any alterations you should contact the Supplier.
Requirement for fitting racking close to floor seams
Q. What are the regulations when there are seams/joints in the warehouse floor and the best practices when it comes to installing footplates close to them.
A. There are no “regulations” with respect to the proximity of rack uprights and anchors to floor slab joints but there are engineering matters that need to be considered.
The reason that concrete floor slabs have joints is that concrete shrinks as part of the curing process and this cannot be prevented. The joints are provided so that the shrinkage takes place in a controlled manner i.e. at the joints, rather than in an uncontrolled manner i.e. random cracking. This shrinkage takes place over many years however, the rate of shrinkage reduces with time and most of the shrinkage will generally take place during the first two years after the slab is laid. So, if your floor slab has only just been laid then you should expect considerable shrinkage, if the slab is less than about 1 year old then you should still expect shrinkage, if the slab is over 2 years old then there should only be a small amount of further shrinkage. This shrinkage is important as it means that the joints will “open up”. Therefore, it is important that the rack designer has considered the joint layout (and potential shrinkage which could have a deleterious effect on the racking) when positioning the racking in the warehouse.
There are two main types of slab joint
•Saw-cut joint – these are typically about 6mm wide and made using a diamond saw after the concrete has initially set.
•Formed joints (often referred to as expansion joints) – these tend to have armoured arises.
For structural reasons the slab designer will normally limit the proximity of rack upright to the joints; this varies from slab to slab but will typically be around 200mm. Some slab designers only limit the proximity of the upright to the formed (expansion) joints whereas others will apply this to all joints. You should contact the slab designer for this information.
The second limitation for the joints is the proximity of floor anchors. The typical floor anchor used in racking installation is a ‘expanding sleeve’ type. This is a device where a cone at the end of the anchor bolt is drawn into a ‘sleeve’ thereby causing the sleeve to expand and grip the concrete around the hole. This type of anchor could ‘burst’ the edge of the concrete if the hole is too close to a joint and, therefore, there are limitations on the proximity of this type of anchor to a joint. The exact distance depends upon the anchor and is available from the anchor manufacturer. A second type of anchor is normally known as a ‘resin anchor’ and this is typically a threaded rod that is ‘glued’ into the concrete hole. Resin anchors can normally be positioned closer to an edge and information is, again, available from the anchor manufacturer. In both cases the capacity of the anchor will reduce with proximity to the joint.
The above are factors that would normally be considered by the rack supplier/designer and would normally be shown on the rack installation drawings.
SEMA Rack Safety Awareness Inspection Courses
SEMA runs a one-day safety course on Rack Safety Awareness and Inspection. These courses are aimed at end users, giving an in-depth look at the need for inspections, how to conduct an assessment and what actions to take when this is completed. These courses are held at the SEMA headquarters in Burntwood, Staffordshire, but arrangements can be made to hold them at the delegates’ premises.
SEMA Approved Rack Inspectors Qualification
This qualification is aimed at professionals who conduct rack surveys as an integral and significant part of their duties. It involves delegates in undertaking an in-depth SEMA Course, together with an examination and practical assessment. CPD will be an important part of the qualification, demonstrating to end users that SEMA Approved Inspectors maintain a high professional standard.
SEMA Publications
SEMA has 26 publications – Codes of Practice, ‘Guides’ and European documents – all of which are available to purchase online. For further information on these documents contact SEMA or visit our website, www.sema.org.uk
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