The verification regime applies to the disarmament, nonproliferation, and counterproliferation objectives of the CWC.

 

The verification regime applies to the Convention’s disarmament objective, chiefly through the oversight of the destruction of chemical weapons stockpiles and facilities. It applies to the Convention’s nonproliferation objective, through the oversight of the veracity of activities not prohibited by the Convention, such as industrial uses. Furthermore, it applies to the Convention’s counterproliferation objective, through the investigation of suspected violations. Chemical weapons disarmament: verificationregime related to the destruction of chemical weapons (CWC Articles III, IV, and V). To maximize States Parties’ adherence to their chemical disarmament obligations, a rigorous process of declarations and verification is applied. This process includes not only existing chemical weapons stockpiles but also old and abandoned chemical weapons. The declaration requirements, detailed in Article III, set the groundwork for compliance. Article IV directly mandates the destruction of declared chemical weapons under strict verification measures based on on-site inspections, as detailed in Part IV of the Verification Annex. At the same time, Article V requires the dismantling of chemical weapons production facilities and prohibits the construction of new ones, also under strict verification measures based on on-site inspections, as detailed in Part V of the Verification Annex. In addition to these chemical disarmament provisions, paragraph 3(e) of Article III also obligates States Parties to declare the chemicals that they hold for riot control purposes. Chemical weapons nonproliferation: verification regimerelated to activities not prohibited by the Convention(CWC Article VI). In parallel with the chemical disarmamentrelated verification regime, a rigorous process of declarations and inspections-based verification is applied to ensure that States Parties adhere to theConvention’s mandate to employ chemistry only for non-prohibited purposes. As explicitly set forth in Paragraph 1 of Article VI, States Parties are indeed entitled to use chemistry and chemicals for purposes that are not prohibited by the Convention. However, as established by the remainder of Article VI and the related portions of the Verification Annex (Part VI to IX), these permissible uses are subject to stringent controls. States Parties must declare the relevant activities and facilities within their jurisdiction, which are then subject to meticulous inspection-based verification measures. The verification regime for these non-prohibited activities is based, in part, on the CWC Schedules, three lists of toxic chemicals and precursors for their synthesis that have been recognized as posing a risk to the objectives of the Convention. Chemicals that present the greatest risk to the objectives of the Convention and are deemed to have minimal or no applications beyond their role in chemical weapons programs are categorized under Schedule 1. As we transition from Schedule 1 to Schedules 2 and 3, the associated risk of the listed chemicals decreases, while their potential for non-prohibited applications increases progressively. The verification regimes for Schedule 1, Schedule 2, and Schedule 3 chemicals are detailed in Part VI, Part VII, and Part VIII of the Verification Annex, respectively. Generally, declaration and verification requirements are triggered if scheduled chemicals are produced or anticipated to be produced above certain thresholds, which increase progressively from Schedule 1 to Schedule 3 to account for the increased legitimate uses of the chemicals. For example, facilities that produce Schedule 1 chemicals for protective purposes are always subject to the declaration requirement, while facilities that produce Schedule 3 chemicals must be declared if the individual amount of any Schedule 3 chemical produced in the previous year or anticipated to be produced in the next year exceeds 30 metric tonnes. Beyond the CWC Schedules, the CWC extends its verification regime to other chemical production facilities (OCPFs), as specified in Part IX of the Verification Annex. Just like for scheduled chemicals, the verification of OCPFs is also dependent on mandatory declarations by States Parties. In particular, OCPFs subject to the declaration requirement are sites that, in the previous year, produced over 200 metric tonnes of unscheduled discrete organic chemicals or over 30 metric tonnes of an unscheduled discrete organic chemical containing phosphorus, sulfur, or fluorine (PSF chemicals). Hence, except for facilities that produce exclusively hydrocarbons or explosives, which are excluded from the definition of OCPFs, the CWC verification regime extensively covers the chemical sector. Historically, the planned number of yearly inspections related to non-prohibited activities outlined under Article VI has been 241, the majority of which targeting OCPF sites; however, this number decreased during the pandemic. For 2024 and 2025, the number of planned inspections has been set to 200 annually, with 130 of these specifically targeting OCPF sites. It is expected that the inspection frequency will return to the normal rate of 241 per year by 2026.57 Chemical weapons counterproliferation: verification regime related to alleged violations of the Convention (CWC Articles IX and X). As discussed, the verification regime applicable to the chemical disarmament and nonproliferation objectives of the CWC is based on routine inspections triggered by declarations from States Parties. Moving to counterproliferation, Articles IX and X of the CWC go beyond routine inspections by establishing mechanisms to trigger inspections in cases of suspected violations. Specifically, Article IX allows for challenge inspections, which can be initiated by any State Party concerned about another State Party’s compliance with the CWC. At the same time, Article X allows a State Party to request protection and assistance if it believes it has been the victim of a chemical weapons attack, that riot control agents have been used as a method of warfare against it, or if it feels threatened by activities prohibited by the CWC conducted by another State Party.58 If a State Party requests a challenge inspection under Article IX to address suspicions of chemical weapon-related activities that do not involve actual use – for instance the production or stockpiling of chemicals for chemical weapon purposes, or the undeclared production of dual-use chemicals subject to declaration requirements – inspection activities to verify compliance with the Convention are conducted according to the procedures set forth in Part X of the Verification Annex. Conversely, if a State Party has initiated a challenge inspection under Article IX to address suspicions of actual use of chemical weapons against another State Party, or submits an assistance and protection request under Article X to address suspicions of actual use of chemical weapons against itself, an Investigation of Alleged Use (IAU) is conducted in accordance with the procedures established in Part XI of the Verification Annex.