Supports in damp locations must be?

Supports in damp locations must be plastic-coated to ensure they resist corrosion and degradation caused by moisture. This is particularly important in environments where humidity and water exposure are prevalent, as untreated metal supports could rust and ultimately fail, compromising the integrity of the installation. The plastic coating acts as a barrier, protecting the underlying material from corrosive elements present in damp conditions.

In contrast, galvanized supports, while treated for corrosion resistance, may not offer enough protection in extremely wet environments over time. Wooden supports can warp, rot, or support the growth of mold and bacteria when consistently exposed to moisture. Uncoated materials, regardless of their composition, are inadequate for damp settings due to their susceptibility to corrosion or decay. Thus, plastic-coated supports are the most appropriate choice for maintaining durability and safety in damp locations.