Storage systems
Racking installation
The requirements for the safe installation of racking vary according to the type and size of the system, and the nature of the building or area for which it is intended. Safe working loads, heights, widths and equipment tolerances should be set by the designers and manufacturers of the total system. The basic principles for safe installation are as follows:
Racking should only be installed by competent people in accordance with the manufacturer’s instructions. A programme of installation training is run under SEIRS (Storage Equipment Installers Registration Scheme), which is run by SEMA. There is more information on the SEMA website.
Racking should be erected on sound, level floors, capable of withstanding the point loading at each base plate.
Where the racking design requires it to be secured to the building, only those building members that have been ‘proved’, by structural calculations, as able to resist the forces applied should be used. In such a case, the racking design should be compatible with the building layout.
Double-sided runs should be connected and spaced using suitable run spacers.
Where necessary, eg where lift trucks or other mechanical handling equipment are used, racking should be securely fixed to the floor (see paragraphs 636–638).
Aisles should be wide enough to ensure that mechanical handling equipment can be easily manoeuvred. Widths will depend very much on the type of equipment used, eg some require a 90° turn to load and offload, some remain parallel to the aisle and have forks at 90° to the direction of travel.
Beam connector locks should always securely fix the connectors at the ends of each beam, to prevent accidental uplift of beams, eg by lift truck.
Racking should have a clear unambiguous notice securely fixed to it, stating the maximum load together with any necessary specified load configurations. A typical notice is shown in Figure 48 and more examples for other types of racking can be seen in the SEMA publication Load notices.50 See also the SEMA publication Recommended practices for the safe use of static pallet racking.51
The limitations indicated in the maximum load notice should never be exceeded. The weight of each palletised load should be established before a decision is made to store it in the racking. This is particularly important where different products are stored which may vary considerably in weight, or where a new line of product is brought into the warehouse for the first time. In some situations, it may not be necessary to establish the weight of each palletised load, if the racking system is designed and installed to meet the storage requirements of the heaviest palletised load in your company’s operation. Nevertheless, you should adopt a system to ensure that all palletised loads intended for storage in racking can be safely stored in accordance with the particular racking design and installation.
Racking should never be altered (eg by welding) nor components removed without first consulting the manufacturer. Before changing the position of adjustable components on racking (as supplied), you should establish the design limitations of the new configuration and, where necessary, amend the safe working load notice. Adjusting the position of the first or second beam from the bottom is normally the most critical alteration, which always requires a check on the rated carrying capacity of the rack.
High visibility colours for key components of the racking, eg horizontal beams, will assist truck operators to correctly position the forks and avoid damage to the racking.
For increased safety, many racking suppliers consider it prudent to secure all uprights to the floor. Floor fixing should be such that the anticipated horizontal shear and vertical tensile forces can be safely resisted. Drive-in and drive-through racks should always be designed and floor fixed according to the manufacturer’s instructions.
Racking protection
Where racking is likely to be struck by lift trucks and other vehicles, it should be protected. Generally, such damage is at the lower levels of the racking – use renewable column guards to minimise the risk of damage from accidental impact. Corner uprights in a run of racking are especially at risk and should be suitably provided with a protective device in a conspicuous colour.
Retrofitting upright protection devices to an existing aisle where they have never been provided can have the effect of reducing the available clearances for fork-lift truck manoeuvres, which can in some circumstances increase the amount of damage caused. Such situations need consideration on a case-by-case basis.
Racking inspection and maintenance
In general, racking is manufactured from relatively lightweight materials and, as a consequence, there is a limit to the amount of abuse that it can withstand. The skill of lift truck operators has a great bearing on the amount of damage likely to be caused. Any damage to racking will reduce its load carrying capacity. The greater the damage the less its strength will be.
To ensure that a racking installation continues to be serviceable and safe, the storage equipment should be inspected on a regular basis. The frequency of inspections depends on a variety of factors that are particular to the site concerned and should be determined by a nominated ‘person responsible for racking safety’ (PRRS) to suit the operating conditions of the warehouse. This will take into account the frequency and method of operation together with the dimensions of the warehouse, the equipment used and personnel involved, all of which could damage the structure. The inspection follows a hierarchical approach using several levels of inspection.
Immediate reporting
As soon as a safety problem or damage is observed by any employee, it should immediately be reported to the PRRS. You should have systems in place for reporting damage and defects.
644 Employees should receive training, information and instruction on the safe operation of the racking system, including the parts affecting their safety and the safety of others.
Visual inspections
The PRRS should ensure that inspections are made at weekly or other regular intervals based on risk assessment. A formal written record should be maintained.
‘Expert’ inspections
A technically competent person should carry out inspections at intervals of not more than 12 months. A written report should be submitted to the PRRS with observations and proposals for any action necessary.
A technically competent person might be a trained specialist within an organisation, a specialist from the rack supplier, or an independent qualified rack inspector.
A programme of rack awareness training is run regularly by SEMA to address the issue of visual inspection and a more formal course is run to qualify expert inspectors under the SARI (SEMA approved rack inspector) scheme.
Normal rack inspections will be carried out from ground level unless there are indications of problems at high level that need investigation.
You should keep a record of inspections, damage and repairs. This could be done in a logbook.
Where damage is identified that affects the safety of the racking system, the racking should be offloaded and controls introduced to prevent it being used until remedial work has been carried out. The following table gives information on the classification of damaged racking.
Classification of damaged racking |
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Risk level |
Status |
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Green |
Requiring surveillance only |
Green level indicates the limit that does not require a reduction in rack carrying capacity or an immediate repair of the system. This would indicate racking components that are considered to be safe and serviceable. Such components should be recorded as suitable for further service until the next management inspection but should be clearly identified for specific re-examination and reassessment at future inspections. Exceeding the green level should be considered damage and causes risk to the racking system. |
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Amber risk |
Hazardous damage requiring action as soon as possible |
This would identify an area where the damage was sufficiently severe to warrant remedial work but not so severe as to warrant the immediate offloading of the rack. Once load is removed from a damaged component, the component should not be reloaded until repairs have been carried out. The user should have a method of isolating such racks to ensure that they do not come back into use until the necessary repairs have been carried out and the equipment certified as safe. For example, use dated adhesive labels, which indicate racks that are not to be reloaded until rectified. Any racking with amber risk category damage should be redesignated red risk if remedial work has not been carried out within four weeks of the original designation. |
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Red risk |
Very serious damage requiring immediate action |
These are situations where a critical level of damage is identified which warrants an area of racking being immediately offloaded and isolated from future use until repair work is carried out. Such repair work would usually be by replacement of the damaged component. You should have a method of isolating areas to ensure that they do not come back into use before the repair work is carried out. For example, a particular bay could be offloaded in the presence of the inspector and roped off to prevent further use. |
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