4.1 The means of closing the flaps of corrugated shipping containers is one of the important decisions for a shipper. It may affect the overall material cost, the labor costs, the packaging equipment costs, and the performance of the box during distribution.

4.2 This practice provides a list of many available procedures for closing, sealing, and reinforcing boxes. Most of these describe a particular packaging material and a particular use of it on a box. Some methods involve package performance testing; any closure or reinforcement which passes prescribed tests (usually on the proposed box and contents) is considered to comply with that section of this practice. Performance-based methods are encouraged because they allow for considerable flexibility in the choice of packaging materials and methods yet provide assurance of a given level of performance.

4.3 A diverse range of methods are described in this practice but relative performance levels are not given. Laboratory package testing such as Practice D4169 and field experience are recommended to rate alternative methods on performance for the intended use.

4.4 The descriptions of materials and methods in this practice provide direction for the procurement of materials and for their common uses on boxes. These descriptions may be sufficient for some specification purposes, but others will require more thorough material and application requirements than those given here.

4.5 The list of methods in this practice is not exhaustive; deviation or variation from the listed methods is possible with the approval of the appropriate parties referencing this practice. Depending on the characteristics of the contents, the specific shipping container, the acceptable package costs, the distribution hazards, and the desired degree of assurance of successful shipment, more stringent methods than those listed may be needed or less stringent methods than those listed may be adequate. The methods described are typical uses of the closure, reinforcing, or sealing materials; many of these materials can be used for other box styles or other methods on boxes but all of these are not included in this practice. Materials for box closure, reinforcement, or sealing are commercially available which have higher or lower performance characteristics than those listed in this practice; these may often be used in a lesser or greater quantity than the described applications of the listed materials.

4.6 This practice assumes the following:

4.6.1 The shipping container and inner packing are properly designed for the contents and the distribution hazards (see Practices D4169 and D5118/D5118M),

4.6.2 Normal, reasonable care is taken in shipment, including storage, handling, loading, and bracing, and

4.6.3 Normal, reasonable care is taken in the application of the closure, reinforcing, or sealing materials to the shipping container.