Warehousing and Materials Handling
Domain 5 tests warehouse layout, slotting, picking methods, cross-docking, and the data discipline that makes warehouse execution work.
Flow and slotting
Core flows are receive, putaway, store, pick, pack, and ship. Cross-docking bypasses storage, but only with accurate inbound timing and labeling. Slot by velocity, cube, and affinity; put high-velocity items in the golden zone to reduce travel. Storage density and accessibility trade off: a fully cube-utilized warehouse can be slow to pick. Pick methods include wave, batch, zone, and waveless; choose based on order profile and cutoff times.
Worked example
Item A is 20% of picks. Moving it from a location 100 ft from the pick face to one 20 ft away saves 80 ft per pick. For 100 picks, travel falls by 20 × 80 = 1,600 ft. At $0.02 per ft, savings are $32 per 100 picks; at 50,000 picks per year, that is 500 × $32 = $16,000. The reasoning is to multiply picks affected by distance saved, then convert travel to labor cost.
Traps that cost marks
Maximizing storage density at the expense of pick productivity; slotting by unit cost instead of velocity; cross-docking without inbound accuracy; ignoring returns and reverse flows; trusting WMS inventory without cycle counts.