The "short name" of the International Organization for Standardization. Based in Switzerland, the ISO sets international industrial standards, including standards for the use of units of measurements. For ISO film ratings, see ASA
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}