This paper describes the challenge of integrating specific types of ECDA indications, such as ACenhanced
corrosion (ACEC) and DC interference (DCI), under the prioritization criteria recommended
by NACE RP0502-2002.
Starting from the observation that the risk of corrosion does not always increase with the size of the
holiday, the paper analyzes the interaction of up to four complementary ECDA indications (i.e. CIPS,
DCVG, ACEC and DCI), with and without prior history of corrosion, as a function of their severity.
New concepts, such as “distributed indication” and “relevant indication”, are introduced in order to
establish the location of the direct examinations, where the indication affects entire sections of line (i.e.
10 km of line subject to severe ACEC).
Simple rules are proposed for integrating these multiple ECDA indications in matrix type prioritization
tables. The paper also includes an example of using these tables to prioritize a combination of three
indications without prior history of corrosion (i.e. moderate DCVG in conjunction with a severe DCI
and a severe CIPS indication).