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ventilation was very good and illustrates the effectiveness of side 

 ventilation. 



The pallet box with solid sides and bottom, but with an air space 

 around the bottom, had the best performance of those boxes where the percent- 

 age of free area is low. It was, however, definitely much slower than the 

 well-ventilated boxes that were included in the same test. 



It is possible that boxes with fiberboard liners could be provided 



with more slots and bring the free area of both bottoms and sides to about 



5 percent. Further work should be done along this line, as there is good 



possibility that cooling performance of this type of pallet box could be 

 greatly improved. 



Recommended Practices in Storage Room 



The handling of pallet boxes in storage should apparently follow the 

 best practices for handling pallet loads of standard boxes of apples. 



Previous studies have shown that when containers of fruit are placed 

 directly against outside walls, heat is transmitted through the wall into the 

 container and there is no opportunity for room air to pick up the heat before 

 it enters the pallet box. Fruit in such locations may be 1 or 2 degrees 

 higher or lower than fruit in adjoining boxes depending on outside temperature 

 Stacks should be at least 6 inches away from outside walls to eliminate this 

 difficulty. Similar space should be left near inside walls. Placing the box 

 against these walls interfers with circulation past the stack and the ability 

 for air to enter or leave the fork spaces. Rows should be run straight, with 

 the aid of floor markers, to provide approximately a 5-inch space between rows 

 of boxes. 



Stack rows should run parallel to the direction of air flow in the 

 storage. Previous tests have indicated that more uniform holding temperatures 

 are obtained when this is done, if 2-way pallets are used in the box construc- 

 tion. A row of boxes constitutes an almost solid dam to the flow of air. 

 Placing the stacks perpendicular to the normal airflow pattern results in 

 interference with uniform airflow. 



Stack rows should consist of similar pallet boxes so the fork space 

 between boxes is continuous from front to back of the row, allowing a con- 

 tinuous air channel. Although boxes may be very close to the same height, 

 the difference is cumulative and at the upper positions in the stack a 1-inch 

 difference in box height can serve to blank off the channels formed by the 

 fork space. 



