Stacks should not be stored above an unsafe height.
- A safe height may be context specific; for NFI cartons/bales/sacks of any size that are heavy enough injure workers, stacks should never exceed 2.5 meters, while light voluminous items such as empty plastic jerry cans might be stored higher if required.
- No matter the height, warehouse workers should be able to safely withdraw cargo from the top layer without risk of falling or causing the stack to collapse.
- A stack should not surpass a ratio of 3:1 - the height cannot be 3 times the vertical length than the horizontal width of the base.
- Stacks should never be so high that they come into contact with the ceiling, and at least half a meter space should be left between the top of the stack and the ceiling for accessing items as needed.
Stacks should never exceed 6 meters in length, or a maximum floors pace of 6 x 6 meters. Excessively wide or large stacks can cause multiple problems: