One large box means fewer lids, labels and handling steps, and a smaller wall area too. Use three 20-litre cubes instead of one 60-litre cube and the total surface grows by about 44 per cent (area grows with volume to the power of two thirds), and with the same insulation thickness so does heat gain. If the route serves three customers, the first stop opens the whole cold volume, and after a partial delivery the product shifts in the remaining void.
The Turkish Manual Handling Regulation (2013, Annex 1) sets no kilogram limit; it counts a very heavy load and shifting contents as risk factors. The weight of the full large box and its balance after partial unloading are therefore worked out separately.
With small boxes every delivery is a closed unit and product families stay apart; the cost is more lids, labels, coolant and a more complex pallet pattern. Load the same order both ways and record closure time, loaded weight, void after the first stop and the number of deliveries fitting one pallet.
