FAILURE OF PLASTIC COMPONENTS CAUSED BY RESPONSE TO COVID 19 PANDEMIC

The response to the COVID-19 pandemic brought changes in the operations of many businesses. A common response since the beginning of the pandemic was an increase in the cleanliness and disinfection of public spaces and products to reduce the spread of the coronavirus. In this effort, businesses and municipalities developed and adopted rigorous disinfection protocols very rapidly. As a result, plastic products in service were exposed to multiple cleaning products such as solvent based cleaning wipes, disinfectant sprays, gels, and detergents. Typically, chemical compatibility between plastic materials and the expected chemicals that would be encountered in service is investigated during the material selection and product development by conducting testing to various industry standards. However, the quick response to the Covide-19 pandemic caused a situation where cleaning products were introduced, in many cases without having the time necessary to perform extensive testing. This has resulted in failures of plastic components from environmental stress cracking (ESC) mechanism.

In this presentation, two case studies of failure investigations involving plastic components that exhibited ESC failure due to cleaning protocols introduced in response to COVID-19 pandemic will be discussed. In the first case study the failure of polycarbonate product from the medical device industry was found to occur. Analysis revealed that the plastic material was failing because of exposure to a cleaning product. Chemical compatibility testing based on ASTM standard test methods was performed to demonstrate the chemical incompatibility. The findings lead to development of standard cleaning processes with compatible chemicals which eliminated the failures. In the second case study a plastic switch knob used in the transportation industry developed failures from ESC. The failure analysis investigation revealed that the product was exposed to multiple cleaning agents. The investigation and testing conducted determined the one specific product that was chemically incompatible with the plastic material.