A Curtain to Help Maintain Temperatures in Local Refrigerated Delivery Trucks

Excerpts from the report Summary: In the summer of 1955, the Department of Agriculture conducted a study of the operation of refrigerated trucks used for local delivery of frozen foods. These studies were made in the cities of Atlanta, Ga. , Washington, D. C. , and Baltimore, Md. Frost melting on the "cold plates" caused considerable dripping inside most of the trucks. Also, the product temperature was considerably higher at the time of delivery than when loaded into the truck. One of the major reasons for higher temperatures inside refrigerated trucks in summer is that warm air enters each time the truck door is opened at a delivery stop. Various types of canvas curtains have been installed inside the rear door by operators of refrigerated trucks in an attempt to reduce this in-flow of warm air. However, because a canvas curtain prevents entry of light and often becomes wet or frozen stiff, it has never proved practicable. The curtain described in this report was developed as a practical solution to difficulties encountered with previous curtains. It consists of 2 weighted halves and is made of a commercially available transparent and tough polyester plastic film reinforced with neoprene coated nylon. A curtain was installed in each of 5 trucks and was tested under actual operating conditions during the summer of 1956.