Tank cars are specialized pieces of equipment. As an example, the interior of the car may be lined with a material, such as glass, or other specialized coatings to isolate the tank contents from the tank shell. Care is taken to ensure that tank contents are compatible with tank construction.

Within the rail industry, tank cars are grouped by their type and not by the cargo carried. Tank cars carrying chemicals or other dangerous goods are generally made of different types of steel, depending on the intended cargo and operating pressure. The tank heads are also stronger to prevent ruptures during accidents.