Preselection, Testing of Polymeric Materials: Advantages and Options

The selection of components, subassemblies and individual materials is a key element in the design of electrical equipment. To reduce the risk of products being delayed to market, product designers need to select materials that mitigate the risks of fire, electric shock, personal injury and environmental hazards, as well as comply with established North American and international safety standards. Preselection is a valuable tool for helping product designers find materials that comply with safety standards. It can also greatly reduce the time and cost associated with final end product testing, thereby speeding time to market. Preselection may also permit the use of alternate materials without end product testing on assembled plastic parts, providing manufacturers the ability to easily substitute alternate materials without incurring additional costs. Recent amendments to the International Electrotechnical Commission's (IEC) standards for household appliances and information technology equipment-IEC 60335-1 and IEC 60950-1, respectively-now permit the use of materials preselection testing as the equivalent or preferred method to end product testing on assembled plastic parts. The revised IEC 60335-1 standard covers preselection for plastic materials located within 3 millimeters of electrical connections within the appliance.