Would the Real -850 mVcsE Criterion Please Stand Up

摘要

Some recent papers contain inaccurate information regarding the validity of the -850 mV_(CSE) current applied criterion, the so-called on-potential criterion. To qualify as a corrosion control criterion the -850mV_(CSE) value must imply a sound engineering judgment of the corrosion rate. Only the -850 mV_(CSE) polarized potential criterion does this, as supported theoretically and empirically through its development, where a corrosion rate of less than 1mpy (< 0.025mm/a) is generally accepted. There is no similar scientific backing for the -850 mV_(CSE) on-potential criterion. Numerous comparative studies of these two criteria illustrate that the corrosion rate can not be judged on the basis of an on-potential criterion when the IR drop is ignored. Failure to correct the on-potential measurement, by removing the IR drop, leaves the public exposed to an unnecessary safety risk.