The UIAA has issued an update warning climbers about the risk of general corrosion as well as chloride stress corrosion cracking (SCC) of anchors in tropical and marine environments. The report explains how in situations where “certain ranges of humidity exist, salt deposits on some types of stainless steel can cause chloride stress corrosion cracking much faster than expected, in some cases within a year of exposure.”
The report also pointed out that, “The affected anchors do not always show any visible signs before their often sudden and potentially disastrous, failure. ”
These new concerns are in addition to usual corrosion issues that arise when dissimilar metals are used for the bolt and hanger resulting in galvanic corrosion.
More details on the UIAA site.