A cryogenic tank is a 10 foot to 40 foot long cylinder shaped thermally insulated pressurized container. It is made from seamless or welded steel and it is encased in a box or beam frame. Cryogenic tanks transport from 4,500 to 5,550 gallons of cryogenic liquids and refrigerant gases, or liquids and refrigerant gases. Denoted as MC-338s, these tankers have a tank with an outer shell made of aluminum or mild steel. Relief valves are located on the top rear of the tank.

Cryogenic materials are gases that have been refrigerated to a temperature that converts them to liquids. Unlike liquefied gases, which use pressure to reduce them to liquids, cryogenic gases are cooled to the point of becoming liquid, and must be kept cool to remain so. The most common materials are nitrogen, carbon dioxide, liquid oxygen, argon, and hydrogen.

The material inside the tank is kept liquid by vacuum. As the truck travels the sun will heat the material, increasing internal pressure. At a predetermined limit, the relief valve will open, relieving any excess pressure into the atmosphere.