Excessive moisture in metal conduits primarily leads to which issue?

Excessive moisture in metal conduits primarily leads to corrosion. When metal is exposed to moisture, it can facilitate chemical reactions, particularly oxidation, which results in the degradation of the metal over time. This process is particularly prevalent in environments where condensation or water ingress is common.

Corrosion can weaken the structural integrity of the conduit, leading to potential failures or hazards in electrical systems. It can also create issues with connectivity and insulation, as corroded surfaces may not conduct electricity as effectively.

In contrast, excessive moisture does not lead to the expansion of the conduit, as metal generally contracts when cool and expands when heated. Rust prevention is not a resultant effect of moisture; rather, moisture promotes rust—a type of corrosion—especially in ferrous metals. Additionally, moisture does not increase the strength of metal conduits but instead contributes to their deterioration. Thus, addressing moisture accumulation is crucial for maintaining the longevity and safety of conduit systems.