The impact of materials on the flammability of printed wiring board products

Despite the fact that appropriate design precautions and materials selection procedures are implemented to ensure the safety of printed circuit board equipment, fires, though rare, can and do occur. Design and manufacture for ultimate product safety reflects the fundamental aspects of the quality process and minimization of the potential for fire during failure requires a high level of appreciation for how design, materials and manufacturing combine to determine product reliability. It is therefore important that equipment designers, manufacturers and component vendors understand the general mechanisms of fires in printed wiring board (PWB) products and further determine how circuit design and materials selection impact the flammability of PWB products. In this paper the author reviews the impact which printed circuit board laminates, solder masks and design rules have on the initiation and propagation of fires in electronic equipment as derived from experimental observations. General recommendations for minimizing the potential for fires in electronic equipment are presented