This year, 2016, World Standards Day was on Friday, October 14. One of the competing official announcements says:
Each year on 14 October, the members of the IEC, ISO and ITU celebrate World Standards Day, which is a means of paying tribute to the collaborative efforts of the thousands of experts worldwide who develop the voluntary technical agreements that are published as international standards.
This year the United States is celebrating World Standards Day on Thursday, October 27.
The U.S. celebration trumpets the year’s international official theme: “Standards Build Trust”. There will be a gala dinner in Washington, D.C., on World Standards Day, to celebrate the day and the theme.
Last year, 2015, World Standards Day was on October 14. The United States celebrated the 2015 World Standards Day on September 28-October 2.