ISO 7001 ("public information symbols") is a standard published by the International Organization for Standardization that defines a set of pictograms and symbols for public information. The latest version, ISO 7001:2007, was published in November 2007.
The set is the result of extensive testing in several countries and different cultures and have met the criteria for comprehensibility set up by the ISO. Common examples of public information symbols include those representing toilets, car parking, and information, and the International Symbol of Access.
References
ISO 7001 Wikipedia(Text) CC BY-SA