A standard for salt mist resistance for solar panels has been set by the IEC or International Electrotechnical Commission. Panels have to meet a standard called IEC 61701 to be suitable for installation near th. There are six levels of corrosion resistance to the IEC 61701 standard. Level 1 is suitable for marine environments such as on roofs by the beach. Level 2 isn't actually used, while level. In a reasonably sheltered area, such as near the beach in Adelaide or in Hervey Bay, there will rarely be salt mist more than 100m from the shore so you will probably be okay without c. Even if you are a good 300m back from the shore and you are pretty confident the location never receives any salt mist, I say you may as well go with corrosion resistant panels anyway. Corrosion affects all metals. Well, all metals except gold. Gold does not corrode under conditions normally found on this planet, so feel free to invite C3PO and Hedonismbotdow.
