Controlled Chemicals

Learn about controlled chemicals under the Chemical Weapons Convention including the schedules, unscheduled discrete organic chemicals and how to determine if your product requires licensing.

Last updated on 13 August 2026

The Chemical Weapons Convention (CWC) classifies toxic chemicals and their precursors into three schedules, along with an additional category called Unscheduled Discrete Organic Chemicals (DOCs).

Chemicals are scheduled based on the risk they pose, with Schedule 1 posing the highest risk. DOCs are not directly related to making chemical agents, but the facilities built for their production (with quantities exceeding threshold limits) can potentially be converted to chemical weapons production facilities.

You can use this table to quickly understand what are some of the chemicals which are controlled, examples, and typical product uses.

Scheduled Chemicals

Overview of Chemical Weapons Convention Schedules, Examples, and Commercial Applications

Schedule/Type	Description	Examples	Possible product categories
Schedule 1	Highly toxic chemicals that could be used as chemical weapons (Schedule 1A), and their final-stage precursors (Schedule 1B). They pose a high risk to the objectives of the Convention and have little or no commercial application.	Sarin Saxitoxin Ricin	Flame-retardant additive research (plastics, resins, fibres) Medicinaland pharmaceutical preparations
Schedule 2	Chemicals that could be used as chemical warfare agents (Schedule 2A and 2A*) or as precursors for chemical weapons (Schedule 2B). They pose a significant risk to the objectives of the Convention and have moderate level of commercial application.	Methylphosphonyl dichloride Arsenic trichloride	Insecticides Herbicides Epoxy resins Flame-retardant additive research (plastics, resins, fibres) Medicinal and pharmaceutical preparations - Metal plating preparations
Schedule 3	Covers chemicals which had previously been produced, stockpiled or used as a chemical weapon. They pose a risk to the objectives of the Convention as they could be used for producing chemicals listed in Schedule 1 or Schedule 2B. Schedule 3 chemicals have widespread commercial application.	Triethanolamine Methyldiethanolamine	Pesticides Insecticides Toiletries Pharmaceutical Metal plating preparations Surfactants for detergents, oil drilling emulsions Corrosion inhibitors Soil fumigants
Unscheduled Discrete Organic Chemicals (DOCs)	Chemicals that belong to the class of chemical compounds consisting of all compounds of carbon, except for its oxides, sulfides and metal carbonates. They are identifiable by name, structural formula (if known), and Chemical Abstracts Service (CAS) Registry Number (if assigned), with certain exclusions. Divided into: PSF-containing (contains phosphorus, sulfur, fluorine) Non-PSF-containing	Varies by product

See the full list (opens in new tab) of scheduled chemicals.

Determining if Your Product is Controlled

Check if your product is controlled by:

Referring to the list of scheduled chemicals (opens in new tab), or
Using the search engine (opens in new tab) with your product description, HS code, or Competent Authority (CA) product code.

If your product is controlled, the CA and the specific chemical(s) will be listed.

Contact the CA directly for licensing requirements.

Need Assistance?

If you are unsure whether your product is controlled, submit a Product Enquiry Form under “Chemical Weapons Convention Forms” on the Customs Forms and Service Links (opens in new tab) page.

Include the following supporting documents:

Safety Data Sheet (SDS)
Certificate of Analysis (CoA)

Required Information:

Applicant details
Activities involved
Product’s HS codes
SDS/CoA
Intended use

Submission Instructions:

If you have multiple files, zip them into a single file.
If your file exceeds 7MB, submit via email customs_nacwc@customs.gov.sg.