Defining count zones: zone plan, sequence and gap control

On count day there are two kinds of error that no count team notices on its own: bins that nobody has counted, and bins that two teams have counted. Both arise when the division of the warehouse is unclear. The solution is count zones: every bin belongs to exactly one zone, and every zone has a sheet, a team and a sequence. This article shows how to build the zone plan, fix the counting route and use a gap control to make sure that nothing is counted twice or not at all.

Rules for the division

• A zone corresponds to what one team can manage in one block of time. As a rule of thumb, 150 to 200 count positions, which at 40 positions an hour is about four to five hours.
• The boundaries are physical: aisle, rack row or room, not "all screws". Anyone who divides by item group has several teams counting the same floor area.
• The boundaries are visibly marked, for example with a sign or barrier tape.
• Places outside the racking are zones of their own: floor storage, cold room, outdoor area, containers, workshop, office, showroom.
• Each zone receives an identifier (A, B, C) in the order of the counting route.

A fictional example: 2,880 count positions divided into zones of 160 positions each give 2,880 ÷ 160 = 18 zones. With six teams each takes three zones, about 12 hours of first count (3 × 4 hours), so one and a half shifts. The second count needs the same effort again.

Fixing the sequence

The counting route is a prescribed round: aisle by aisle, within the rack from left to right and from top to bottom or the reverse, but always the same. The teams start at different ends so that they do not meet in the aisle. In the second count the direction changes, and a different team counts. Sensitive or valuable areas are counted first, while concentration is high. Counted zones are visibly marked "counted", with time and team initials, and movements in them are recorded separately.

The gap control

The basis is a register of all bin locations, preferably from the system and supplemented by a walk-through. Each count sheet names the bins it contains. After the count the sheets are matched bin by bin against the register. Important: simply comparing the number of lines is not enough, because a gap and a double count cancel each other out.

A fictional example: the plan has 2,880 bins. The analysis of the sheets shows 2,866 bins that appear exactly once, 6 bins on two sheets and 8 bins on none (2,866 + 6 + 8 = 2,880). Together the sheets contain 2,866 + 12 = 2,878 lines and differ from the planned figure by only 2. The line comparison therefore reports "almost fine", although 8 bins are uncounted and 6 counted twice. Only the bin-by-bin comparison finds both.

Typical causes: newly set up bins that are missing from the register, bins on a zone boundary, bins behind a door, in the office or in the yard, and empty bins that nobody has entered. Empty bins are confirmed as "empty".

Final walk-through

Before the count is regarded as complete, the count leader and a second person walk through all zones. They check whether every zone is marked as counted, whether goods are standing in the aisle or on boundary areas, and whether labels or bins are missing. The result goes into the record.

In short

A clear zone plan with sequence and gap control turns the count into a closed system: every bin has a zone, every zone has a sheet. Before every assignment AuditMaster fixes zones and counting route and, on request, labels racks and bins as the basis for every count.