This part of ISO 15223 specifies a process for developing, selecting and validating symbols for inclusion in ISO 15223-1. The purpose of this part of ISO 15223 is to ensure that symbols included in ISO 15223-1 are readily understood by the target group. If the symbol validation process detailed in this part of ISO 15223 has been complied with, then the residual risks, as defined in ISO 14971 and IEC 62366, associated with the usability of a medical device symbol are presumed to be acceptable, unless there is objective evidence to the contrary. This part of ISO 15223 is not restricted to symbols intended to meet regulatory requirements or specified in regulatory guidelines on labelling.