Internal corrosion in pipelines is difficult to locate and measure due to a number of factors. Most internal corrosion detection measures require access to the internal of a pipe for inline inspection and visualization tools such as inline pigs, and a substantial portion of the pipeline does not allow inline inspection mostly due to physical and mechanical constraints. Other inspection techniques such as ultrasonic technology and radiography are implemented to measure wall thickness and estimate metal loss from the outside of a pipe, but excavation, cleaning, and other physical constraints allow for only a small area to be inspected at a time.

The ICDA approach to evaluate the likelihood of water accumulation and internal corrosion, and identify critical zones can enhance the actual measurement techniques and ensure safe operation of natural gas pipelines. A detailed analysis of critical locations where water would most likely accumulate provides information about the other parts of the piping system.

Moghissi et. al discuss in the detail the procedure for a ICDA approach. A two tiered procedure has been outlined. The first step deals with identifying the zones with inclination greater than the critical angle and selecting the first such segment. Performing detailed examination of this segment for corrosion forms the second step. If on inspection no corrosion is found, it is concluded that downstream corrosion is unlikely. Performing inspection at the highest inclination upstream of the initial location will provide integrity information of the pipe between these two points. Progressing upstream, identifying susceptible segments and inspecting these segments, the entire pipeline is assessed for internal corrosion.

If the locations identified as most susceptible to internal corrosion are determined to be free from damage by examination, the integrity of a significant part of the pipeline system is assured. If such locations are found to be experiencing corrosion a potential integrity problem is identified.