• If a facility’s chemical substance is subject to a SNUR and the facility’s intended manufacture, processing, or use of the substance is a significant new use, the facility would be required to submit a SNUN 90 days prior to the manufacture of that substance.

To facilitate determining whether a substance is subject to a significant new use rule (SNUR), substances on the Toxic Substances Control Act (TSCA) Inventory that are subject to SNUR requirements are designated as such by an “S” flag in the Inventory listing. If a facility’s chemical substance is subject to a SNUR and the facility’s intended manufacture, processing, or use of the substance is a significant new use, the facility would be required to submit a significant new use notice (SNUN) 90 days prior to the manufacture of that substance.

Note that, according to 40 CFR 721.63, any facility subject to an “applicable” SNUR must determine and use appropriate engineering and administrative controls BEFORE using personal protective equipment (PPE) for worker protection. It is considered a significant new use NOT to implement this hierarchy of controls to protect workers when required. Where engineering and administrative controls are not feasible or are insufficient to protect exposed workers, facilities that are subject to an applicable SNUR must follow any applicable PPE requirements or submit a SNUN to the Environmental Protection Agency (EPA ).

Similarly, according to 40 CFR 721.72, any facility subject to an “applicable” SNUR must establish a written hazard communication program. It is considered a significant new use NOT to establish this written program when required. Where a hazard communication program is not established, facilities subject to an applicable SNUR must submit a SNUN to EPA.

Other significant new uses of chemical substances, which are identified in 40 CFR 721 subpart E, are described in 40 CFR 721 subpart B. These significant new uses relate to industrial, commercial, and consumer activities; disposal; and releases to water. The provisions of subpart B apply only when referenced as applying to a chemical substance identified in subpart E of 40 CFR 721.

Several steps should be followed to ascertain the TSCA Inventory/SNUR status of a chemical substance. Information on non-confidential chemical substances can be found in the TSCA Inventory. Because the chemical identities of the chemical substances can be claimed to be Confidential Business Information (CBI), the Environmental Protection Agency (EPA) maintains a CBI version of the TSCA Inventory. If an intended manufacturer submits a premanufacture notice or a notice of bona fide intent to manufacture (pursuant to the procedures at 40 CFR 720.25 or 721.11) on a substance that has a listing on the Confidential Inventory, the agency will notify the submitter of the existence of the SNUR and identify any confidential significant new use designations.

It is always the obligation of the manufacturer or processor selling a chemical substance to notify the user of the SNUR status of that substance. Buyers of a chemical substance whose identity is confidential, and thus not disclosed to them, should seek certification from the sellers that their intended use is not a significant new use.