Thanks to French Cemafroid institute ECLER for this handy and informative guide to responsible temperature-controlled distribution.
For valuable energy saving advice for refrigerated vehicles, have a read of this good practice guide to distribution and unloading goods by the ECLER program (Economie Circulaire, Logistique Ecologique et Responsable). 
In addition to featuring BlueSeal air curtains as a way to regulate heat loss during loading/unloading, this is a must-read guide for temperature-controlled logistics that helps operators to preserve valuable energy when transporting cold goods.

Read at https://dataform.cemafroid.fr/programmes/2033413a-d97f-4c4f-9eaf-356cae850f5a/modules/a2ac368e-e839-420d-b1d3-730e48cbabb4/sequences/44bcfa31-72c6-42a3-a78f-1c6dcc76aa47