A tremendous amount of financial loss is incurred every year as a result of premature failures of roofing materials, galvanized steel, aluminum, stainless steel, copper, paints and coatings. The cost to repair such failures far outweighs the initial costs, since excessive rigging may be needed to access the failing areas. Additional liability may also be expected if a facility must stop operation for the necessary repairs to be made.
A determination of the fundamental causes behind failures is critical. Not only does this help in assigning financial responsibility, but knowing how a roofing has failed is often the first step in planning how to fix it. To investigate a failure, and analyze the conditions that promoted the failure, important information must be collected on the failed paint or coating.
A failure analysis investigation is much like the work of a detective. Clues or relevant facts pertaining to the investigation must be gathered, analyzed, explored, and studied to make a knowledgeable determination. As in the case of a good detective, first hand field experience is of the utmost important, yet academic studies are also essential. Failure Analysis – Sequence of Events Justification for conducting paint or coating failure analysis investigations is the most important issue for a failure analyst. The failure analyst should question why failure occurred, how to get the building, facility, or equipment repair coated quickly if necessary, how to prevent a recurrence of the problem, and if more information is needed, how can the information be readily obtained. With these steps taken a plan of attack can be formed.
Our accelerated exposure testing is complemented with electrochemical impedance spectroscopy (EIS). In the EIS technique capacitance and electrical properties of the coating are measured as a function of time. If the impedance ratio does not change as a function of time, then one can with high degree of confidence conclude that the coating is not altered and performs very well under actual service conditions. The advantage of this technique is that we will not accelerate the test such that conditions will result in the failure of coating system. The test will provide reliable data in a short time of exposure. The data from this test can also provide data for calculating permeation rate and minimum coating thickness and cure schedule requirements for adequate corrosion resistance. Analysis of the evidence, and a review of the existing data and documentation are the final stages of failure investigation. All information is gathered and analyzed to form a determination on the mode and probable cause of the failure. Identification of the mode and cause of failure provide the source for recommendations for corrective action.
A final report including all relevant data, analyses, and recommendations are compiled and presented to the client. In litigation investigations, the client may not be interested in the recommendations section of the report.