apples in such bags to be more susceptible to damage from handling and trans- 

 portation jolts and impacts. This accounted in a large measure for the greater 

 increase in the bruising rates for the apples in plastic-film bags in the 

 master boxes than for the apples in cell -pack boxes. 



The inspections at destination revealed that some of the cell -pack boxes 

 of 120- and 140-count apples in several test loads did not have bottom pads. 

 As a result, the protruding staples in the bottom flaps of the boxes punctured 

 and seriously bruised the bottom layers of apples, especially during transit 

 when the boxes were subjected to transportation impacts and vibrations trans- 

 mitted to them by the movement of the trailer over the road. 



Other conditions which may have contributed to some degree of bruising 

 damage were: (a) Grading operations at the packinghouse; (b) the amount of 

 pressure to which the fruit was subjected during packing; (c) excessive over- 

 head weight from stacking boxes too high on pallets in the warehouse or too 

 high in the trailer loads; (d) unnecessary roughness in handling the boxes 

 during loading into the trailers; and (e) rearrangement of the loads in transit 

 by the truck drivers . 



Principal Location of Container Damage in Trailers 



Damage to the apple boxes in transit was most prevalent at the rear of 

 the trailer on the overhang behind the tandem axles. It is in this area that 

 most of the force of the vertical impacts from the trailer passing over bumps 

 and rough places in the road is concentrated. Generally, the two bottom layers 

 of the last two or three stacks in the load had a tendency to shift back toward 

 the rear of the trailer while the top layers of the same stacks shifted slightly 

 forward compressing the boxes ahead. This forward movement probably resulted 

 from a tightening up of a slight slack existing at the time of loading (fig. 4). 

 The forward shifting of the upper layers caused the boxes in those layers of 

 the rear stack to pull away from the load-locking devices behind and thus where 

 this occurred the load locks were ineffective in holding the upper layers 

 tightly in place. 



The backward shifting of the bottom layers of the last stack can be 

 prevented by adequate bracing in the space between the end of the load and 

 the rear door. This bracing eliminates the voids between boxes in the lower 

 two layers of the last three stacks into which the boxes of the upper layers 

 can tilt and become damaged. Figure 5 illustrates the forward movement of 

 the top layers of the rear stacks and also a simple and inexpensive method of 

 preventing the lower layers from moving toward the rear door and blocking the 

 circulation of air. 



Another efficient and economical method of bracing the rear of a load 

 involves the use of an adjustable endgate with load locking devices behind 

 it as shown in figure 6. A removable gate covering the entire rear of the 

 load with load locks behind it would also have been effective in keeping the 

 load from shifting back toward the rear doors. 



14 - 



