A review of differing approaches used to estimate the cost of corrosion (and their relevance in the development of modern corrosion prevention and control strategies)

Purpose To analyze the different approaches used to estimate the cost of corrosion and understand the limitations so as to have proper appropriation in future appraisals. Design/methodology/approach Four well-known approaches to analysis of cost of corrosion viz., the Uhlig method, the Hoar method, NBS-BCL input/output method and net present value method have been considered in great detail and the impact of these approaches on corrosion economy in different countries has been highlighted. Findings Uhlig method of estimating corrosion cost always gives a conservative estimate of the direct cost of corrosion. The direct cost of corrosion, as estimated by the Hoar method, is found to be somewhat higher than is the estimate made using the Uhlig method, as shown by Shibata of Japan. The NBS-BCL method of input/output analysis, though apparently more scientific, is subject ultimately to uncertainties in quantifying the capital cost and intermediate output. The net present value method appears to be more realistic than do other approaches as it enables a life cycle costing of each structure/facility to be made and arrives at the most cost-effective corrosion control method. Even though all the above four approaches enable an estimation of direct cost of corrosion, there is no standard approach to assess the indirect cost of corrosion. Originality/value In a developing economy, each and every industry has to go for systematic corrosion auditing in order to identify and adopt the most appropriate corrosion control measures and effect considerable savings. This paper would be of immense use in that regard.