Computer simulations and tests have been carried out by LauritzenCool and York Marine AB to confirm the suitability to distribute air in refrigerated cargo holds without gratings. The investigated grating-less concept was confirmed successful by full-scale transports of bananas in a regular service over a period of half a year from Central America to Europe. The work has given valuable information in developing formulas and algorithms to design safe systems for grating-less holds in refrigerated ships. The project started in 1994 with laboratory work at ABB Ventilation Products to find criteria for the rate of cooling of bananas on single pallets. Soon, tests moved on to trials to determine the rate of cooling and temperature gradients in several pallets of bananas and citrus.