Failsafing devices (or poka-yoke devices) are used to inspect the conditions for high quality production (source inspection) or for inspecting work as it is completed to provide the fastest possible feedback (self-checks). These techniques involve 100% inspection and are economical only if the cost of inspection is very low. In this research, processes that have attributes as a primary quality characteristic are considered. An existing model for the economic design of np-charts will be used to determine how low inspection costs must be before self-checks become economical. An existing model for checking proper operating conditions will be used to find how low the cost of source-inspection must be in order for it to be economical.