Rack and bin labels: structure, size and legibility

A bin label seems a small thing until it is missing. Then the count team looks for the goods that the system says are in bin A-03-12-2 and finds neither the rack bay nor anyone who knows it. Labels are the basis of every count, because they turn a hall into a grid in which every location has an unambiguous address. A good bin label is unambiguous, legible from two metres away and stands up to daily warehouse life. This article shows how to build the bin number, what to watch for with size and barcode, and which mistakes occur most often.

Structure of the bin number

A bin number is built like an address, from coarse to fine: hall or zone, aisle, rack bay, level. A fictional example: A-03-12-2 means hall A, aisle 03, bay 12, level 2. These rules apply:

• The same length and the same separators for all bins, with leading zeros (03 instead of 3), so that sorting works.
• No characters that can be confused: no O next to the 0, no I next to the 1.
• Ascending numbering along the walking route. In two-sided aisles, odd bays can lie on the left and even bays on the right.
• Levels from bottom to top: 1 is the floor level.
• The label belongs to the bin, not to the item. The number does not change when different goods stand there.

A calculation example (fictional): hall A has 6 aisles with 40 rack bays each, 20 on each side, and 4 levels, so 6 × 40 × 4 = 960 bins. With a 10 per cent reserve for misprints and replacements, 960 × 1.1 = 1,056 labels are ordered.

Size and legibility

The following figures are rules of thumb from practice. Test them on your own racking.

• The bin number is in plain text, at least two to three centimetres high, so that it can be read from about two metres.
• Strong contrast: dark print on a light background, on matt material that does not reflect.
• Always in the same place, ideally on the beam below the bin. A larger print suits high levels.
• Durability: dust, summer heat and cleaning must not attack the adhesive or the print.
• One label per bin, on the side from which counting is done.

Barcode: when it pays off

A barcode pays off if you scan, or want to scan in future. It contains exactly the bin number, and the plain text sits beside it. Watch for a clear margin around the code, adequate size and a flat surface for sticking. Before printing, test a sample of labels with the reader used in daily work, including on the top level and in corners with poor light. If you do not scan, you count by the plain text. A barcode without plain text is a risk as soon as the label is damaged.

The most common mistakes

• The label is hidden by goods or a post.
• It is stuck on the pallet instead of the rack and moves with the goods.
• Two halls use the same bin number.
• Handwriting replaces the printed label and becomes illegible after a month.
• After a rebuild, labels and system no longer agree.
• Print and barcode are too small because the label was designed to fit the rack, not the counter.

Labelling and checking

It is best to stick labels in one pass per hall, with the bin list in hand, and to have them checked by a second person. Then the bin list is reconciled with the system register: bins that exist in the warehouse but not in the system, and the other way round, are cleaned up before the first count. Spare labels are kept in stock and issued, not stuck on freely.

In short

An unambiguous, legible label saves minutes per bin at every count. AuditMaster labels racks and bin locations with barcode labels, providing the basis for every later count.