Dry ice is widely used for airline shipping and is identified by a Class 9 UN1845 label. We supply these labels on our online store. For assistance calculating how much dry ice you will require, please contact our team with the internal dimensions of your storage container and the expected shipping time. As ambient temperatures can impact the longevity of the dry ice, we recommend using slightly more dry ice than you expect to need or using a Thermosafe Insulated Shipper. These are available in two different sizes and because they offer a greater level of insulation they will hold the dry ice for a longer period of time.