General Guidelines for Strength, Label Placement and Related Information for Large Shipping Boxes
This post outlines some general guidelines and recommendations when choosing the right large shipping boxes for your goods. It will use the previous example of a large and heavy electronics item placed in a 20x20x20-inch box. This post also assumes that previously-discussed proper packaging best practices have been followed and room inside the case has been allocated accordingly.
For such an item the most appropriate is a single-wall 250 burst strength box. It should be new and be rated to 350-lbs per square inch burst strength (pressure at which the material will burst and not survive – usually printed on the package). Viable alternative for this example can be double-wall large shipping boxes with 44 lbs per square inch edge crush test or ECT. ECT is the probable force which would crush a box on its edge – it is a performance test which, among other factors, measures the ability of a box to stack. It is measured in pounds per linear inch.
Once proper weight and packaging requirements are met, the box has to be properly sealed. Use of packaging tape is recommended. Another good kind is filament or strapping tape – it combines plastic straps making the tape extra strong. Use of masking, cellophane, duct etc. tape should be avoided since they serve a different purpose. Regular slotted containers (the most popular kind where the flaps meet in the middle) should have a total of six strips of 2-inch tape (48 mm) applied to both top and bottom of the large shipping boxes. All seams should be sealed to allow for transportation safety. Packaging tape should be slick so that boxes can slide along belts, truck bodies, carts etc.
Labeling convention for large shipping boxes is relatively simple – there should only be one visible address. It should be clearly typed and intelligence on the side of the person handling your boxes should not be assumed or relied on – you do not want a box meant for Berlin, Germany to end up in Berlin, Maryland. If a packaging slip is used, it should go on the same side of the box where the address is. If using an older box – make sure that all other addresses are illegible and crossed off. Do not place labels or slips on the edge of the box and use markers etc which are not water soluble in case of a spill over the box. Placing a duplicate of the source and destination address is an excellent habit which could save you trouble down the line.