The Day of Remembrance for all Victims of Chemical Warfare is an annual event held on April 29 as a "tribute to the victims of chemical warfare, as well as to reaffirm the commitment of the Organization for the Prohibition of Chemical Weapons (OPCW) to the elimination of the threat of chemical weapons, thereby promoting the goals of peace, security, and multilateralism." It is officially recognised by the United Nations (UN) and has been celebrated since 2005. On the 2013 observance day, the UN Secretary-General Ban Ki-moon gave a speech where he stated: "On this Remembrance Day, I urge the international community to intensify efforts to rid the world of chemical weapons, along with all other weapons of mass destruction. Let us work together to bring all States under the Convention and promote its full implementation. This is how we can best honour past victims and liberate future generations from the threat of chemical weapons."
The Conference of the States Parties at its Tenth Session PDF (paragraph 23.3 of C-10/5, dated 11 November 2005) decided that a memorial Day of Remembrance for all Victims of Chemical Warfare would be observed on 29 April each year — the date in 1997 on which the Chemical Weapons Convention entered into force.
The Conference of the States Parties of the Organisation for the Prohibition of Chemical Weapons (30 November – 4 December 2015, OPCW C-20/DEC.10):
1. Decides to designate 29 April each year—the date in 1997 on which the Convention entered into force—as the International Day for the Foundation of the Organisation for the Prohibition of Chemical Weapons (“OPCW Day”);
2. Decides that the Day of Remembrance for all victims of chemical warfare will be held on 30 November each year or, when appropriate, on the first day of the regular session of the Conference; and
3. Decides that the above arrangement will commence in 2016.