Chemical Weapons Convention
The Chemical Weapons Convention (CWC) is an international arms control treaty, in force since 1997, which prohibits the production and use of chemical weapons, requires the destruction of existing chemical weapons, and regulates facilities and substances that can be used to produce chemical weapons. It is the successor to the 1925 Protocol for the Prohibition of the Use of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare.
The CWC, known formally as the "Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction," is intended "to exclude completely the possibility of the use of chemical weapons." Signatories to the Convention have agreed not to produce, use, prepare to use, or help others to use chemical weapons. They have committed to destroying all chemical weapons existing in places under their direct control, as well as any they may have abandoned in places controlled by other signatories. They have also agreed to destroy any chemical weapons production facilities they own or control, and to refrain from using riot control agents as weapons of war.
Nations that have ratified or acceded to the CWC do so by depositing the appropriate signed documents with the Secretary General of the United Nations. They thereby become members of the Organisation for the Prohibition of Chemical Weapons (OPCW), having the right to vote and the obligation to provide financial support. The OPCW's inspectors and staff monitor and report on members' compliance with the CWC.
Upon becoming a party to the CWC, a state must declare the chemical weapons and CW production facilities under its control. It must make and execute a plan for destroying its declared weapons and facilities. It must also demonstrate its compliance with these requirements by cooperating with site inspections conducted by the OPCW's Technical Secretariat. For declared CW facilities, site inspections are routine, and are governed by negotiated agreements between the OPCW and the national governments responsible for the facility in question.
If a member has evidence that another member is engaged in activities forbidden by the CWC, it may seek to initiate a "challenge inspection", a short-notice intrusive inspection of sites that may or may not have been declared. There have been no challenge inspections to date.