Atmospheric Corrosion Classes & Maintenance Intervals (Q&A)
大气腐蚀分级与维护周期问答
标签：大气分级, 维护周期, ISO 9223, 巡检
问：户外铜件多久该维护一次？答：按 ISO 9223 大气腐蚀性分级 C1–C5：乡村 C2 首检 5 年、城市 C3 首检 3 年、工业/海岸 C4–C5 首检 1–2 年；分级依据是铜第一年失厚（C2 约 0.5 μm、C5 约 2.7 μm）。巡检三看：看光泽是否全面变哑（封护失效）、看绿锈是否点状凸起（活性腐蚀）、看排水位污垢堆积（缝隙腐蚀源）。分区分级维护可比统一周期省 40% 预算。
How often should outdoor copper be serviced? Use ISO 9223 corrosivity classes C1–C5: rural C2 first check at 5 years, urban C3 at 3 years, industrial/coastal C4–C5 at 1–2 years—based on first-year copper loss (C2 ~0.5 μm, C5 ~2.7 μm). Inspect three signs: uniform loss of gloss (sealer failure), raised green spots (active corrosion), and dirt dams at drainage lines (crevice sources). Zoned maintenance saves ~40% versus one fixed schedule. ---