Abstract: Apparatus and methods for monitoring localized or pitting corrosion of metal or other material are described. A probe having a working electrode made of the same material as the material being monitored is located in the same corroding environment as the material being monitored. The electrochemical noise detected between the working electrode and other electrodes is processed to provide an indication of the state of localized corrosion of the material being monitored. An anodic bias voltage is applied to the working electrode. This bias voltage accentuates localized corrosion at the working electrode, improving sensitivity and permitting more accurate evaluation of the electrochemical noise signals.

Abstract: A conductometric gas analysis cell comprised of a porous Teflon membrane supporting interdigited electrodes separates a thin layer of deionized water from a gas phase to be analyzed. Volatile species in the gas phase pass through the membrane and increase the conductance of the water which results in increased current flow between the interdigited electrodes.