What type of cross connection exists if the spout on a sink faucet extends below the overflow rim?

The type of cross connection described, where the spout on a sink faucet extends below the overflow rim, represents an indirect cross connection. An indirect cross connection occurs when there's a physical separation between the potable water supply and potential contaminants, but the design allows for the possibility of backflow if the water were to drain back into the system.

In this scenario, if the water in the sink were to backfill or flood, contaminated water could flow back into the spout from below the overflow rim, which compromises the safety of the drinking water. Therefore, the presence of the spout below the overflow rim creates a scenario where contaminants could potentially enter the potable supply if conditions such as backflow or siphoning occur.

This distinction is critical in plumbing systems to ensure that contamination is prevented, and it highlights the importance of following proper codes and standards in plumbing design and installation.