Controlled atmosphere containers on a two-way basis
A different approach to maintaining the integrity of the cool chain in transporting pharmaceuticals by air has been adopted by Swedish company Envirotainer, a pioneer of active temperature control systems. Dry ice is used as the temperature-controlling medium and an internal fan controlled by a sensor circulates cooled air around the inside of a container made from high performance insulation material.
Envirotainer's latest innovation is the CLD container, designed in collaboration with the pharmaceutical industry specifically for the air transportation of small-volume shipments of temperature-sensitive products, such as diagnostics, vaccines, blood fractions and hormones. Its active control system maintains a stable interior temperature for up to 84 hours and uses two internal fans: one to cool warm air by passing it across the dry ice reservoir and back into the container; and the second to circulate the cool air around the product when the temperature is within the desired range. The dry ice and battery are contained in a separate compartment from the product and can therefore be replaced to extend the operational period without having to open the main container.
The CLD measures 101 x 76 x 80cm (LxWxH) and has an internal usable capacity of 0.17m3. It has a tare weight of 72kg and a maximum gross weight of 400kg, giving a maximum load of 328kg. The containers themselves are made from a very strong composite material that is a highly efficient insulator and have extra reinforcement on the corners. A large lid facilitates loading, and the stackable containers are designed to be carried by forklift or pallet truck. They fit onto standard air-cargo pallets and can be used on both wide- and narrow-bodied aircraft. They are also rain- light- and air-tight and the stainless steel locks can be sealed.
One-trip insulated systems have a number of disadvantages, according to Tony Wright, senior vice president, perishables business. They can be complex to prepare and labour-intensive to pack; insecure while in transit; and have a relatively short life, requiring appropriate disposal or recycling after a few trips. They also need to be revalidated should there be any change in the distribution schedule, such as a rerouting through a different stop-over place, and there is a risk that a lengthy delay could result in failure of the cooling element and consequent product wastage. Active control systems, on the other hand, can cope with either eventuality merely by replacing the battery and replenishing the dry ice reservoir.
Initially the CLD containers are being offered by Envirotainer on a two-way lease basis (i.e. pick-up and return to same destination) for a minimum period of seven days. However, it is understood that one-way leasing is being considered for the future. The company is also offering three different validation support packages.