Fail-safes in nanotechnology are devices or features integrated with nanotechnology which, in the event of failure, respond in a way that will cause no harm, or at least a minimum of harm, to other devices or personnel. Fail-safe principles are governed by national standards and engineering practices, and are widely used in conventional engineering design. It is possible to scale down macro-scale fail-safe principles and devices for similar applications at the nano-scale. The use of fail-safes in nanotechnology applications supports social acceptance of those applications by reducing the risks to users; as of 2009, there are both theoretical and practical ways to implement fail-safe designs in nanotechnology.