The type of tank used in a closed-loop piping system can influence the level of contact between the system and the environment. For example, an open-top tank may allow for some air contact, whereas a sealed tank would minimize air exposure. However, even with some air contact, closed-loop systems are still considered closed to the environment due to the limited interaction. The tank design and materials used can also impact the system’s overall performance, corrosion resistance, and maintenance requirements.