What is the primary concern when installing rivets in conditions that could lead to actual electrical differences?

The primary concern when installing rivets in conditions that could lead to actual electrical differences is electrolytic action. This phenomenon occurs when two dissimilar metals are in contact within the presence of an electrolyte, such as moisture. In such scenarios, an electric current may flow between the metals, leading to corrosion of one of the metals, typically the more anodic one.

When rivets are used in structural applications, the possibility of galvanic corrosion becomes significant, especially in environments where corrosion is facilitated by moisture. Therefore, recognizing and mitigating potential electrolytic action is crucial to ensure the longevity and structural integrity of the joint.

Other options focus on factors that are important in different contexts. The tightness of rivets pertains to mechanical integrity but does not address the electrochemical reactions that occur due to electrical differences. Material compatibility is vital in terms of structural performance and mechanical fit, yet without dissimilar metals, the risk of electrolytic action diminishes. Surface corrosion is a general concern but does not capture the specific risks posed by differential electrical potentials between materials.