Regular maintenance/cleaning of fuel pipeline and system hardware is an essential requirement in fuel cell operation to prevent contamination. An experimental and analytical study is performed to aid the selection of appropriate cleansers to be used as cleaning agents in polymer electrolyte fuel cell (PEFC). Screening tests for several cleansers are carried out during the injection of samples into the PEFC cathode inlet. One proper agent (naphtha) has shown a fully recoverable and minimal effect on the fuel cell performance and as such is determined as the best cleansing agent. Unlike other samples, naphtha does not contain any metallic components such as sodium or potassium in its composition. Furthermore, PEFC can still operate at similar to 0.4 V at constant current (1 A/cm(2)) even with a considerable flow rate (250 mu l/min) of the selected cleanser. Detailed analytical analysis of this cleanser is provided by curve fitting the electrochemical impedance spectroscopy data, and evaluation of binary gas diffusion coefficients. It is indicated that performance loss during naphtha exposure is mainly due to the adsorption of contaminants on active Pt sites and an increase in mass transfer resistance. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.