The final rule turns existing TSCA Order restrictions into SNUR triggers
EPA has finalized Significant New Use Rules under TSCA section 5(a)(2) for chemical substances that were previously the subject of premanufacture notices and are already subject to TSCA section 5(e) Orders.
The final rule, Batch 24-5.5e, amends 40 CFR Part 721 and takes effect on October 26, 2026.
The underlying TSCA Orders already impose conditions intended to control potential unreasonable risk for the original PMN activities. The SNURs extend the regulatory gate to future manufacturers, importers, and processors that may seek to use the substances outside those controlled conditions.
A 90-day SNUN does not create an automatic start date
A person intending to manufacture, import, or process one of the covered substances for a designated significant new use must submit a Significant New Use Notice at least 90 days before commencing the activity.
That advance notice is not an automatic authorization after 90 days.
The significant new use may not begin until EPA has reviewed the SNUN, made the appropriate TSCA determination, and taken any actions required by that determination.
For project planning, the SNUN should therefore be treated as a regulatory review gate rather than a fixed 90-day waiting period.
The significant-new-use conditions vary by substance
The final regulatory text does not apply one universal condition to every chemical.
Depending on the individual substance and underlying Order, significant new uses may involve:
- workplace exposure and respiratory-protection requirements;
- hazard communication requirements;
- restrictions on industrial, commercial, or consumer activities;
- air or water releases;
- disposal conditions;
- inhalation-exposure scenarios; or
- restrictions on concentration or the specific permitted end use.
For example, some entries define any manufacture, processing, or use resulting in inhalation exposure as a significant new use. Others incorporate specific respirator protection factors, hazard statements, release controls, or formulation limits.
Companies therefore need to map the actual PMN substance to its specific 40 CFR Part 721 provision rather than applying a generic SNUR threshold.
Not every proposed entry was finalized in this action
EPA states that it is not finalizing the proposed SNUR for PMN P-22-0126 because new information requires further review.
EPA also notes that P-22-0187 will be addressed separately after new information required additional review.
This distinction is useful for supply-chain screening: appearing in the 2025 proposed batch is not sufficient evidence that a final SNUR now applies. The final regulatory text and the individual PMN entry remain the operative compliance reference.
Why this can matter to medical-device supply chains
The rule does not regulate finished medical devices as a device-market-access measure.
Its relevance is upstream. Medical-device manufacturers may rely on resins, coatings, adhesives, silicones, metal oxides, additives, and other functional materials whose U.S. manufacture, import, or processing is subject to a TSCA SNUR.
A supplier statement that a chemical is already lawful in U.S. commerce does not establish that every new process or use is permitted without further review. The important question is whether the actual activity remains within the conditions reflected in the TSCA Order and final SNUR.
What companies can check
- Obtain the PMN number, CAS or accession number, and applicable 40 CFR Part 721 provision from relevant suppliers.
- Compare the current manufacturing, import, processing, and use conditions with the restrictions incorporated into the SNUR.
- Check whether a proposed process change affects inhalation exposure, PPE, hazard communication, environmental release, disposal, or formulation concentration.
- Build SNUN and EPA review time into project plans where a significant new use may be triggered.
- Add TSCA SNUR review to material change-control workflows for relevant U.S. supply chains.
For medical-device companies, Batch 24-5.5e belongs primarily in materials and supplier change control. The critical event is not simply the presence of a regulated chemical, but a new use or process that departs from the conditions EPA has already reviewed.
Sources
- Primary official sourceSignificant New Use Rules on Certain Chemical Substances (24-5.5e) (opens in a new tab)U.S. Environmental Protection Agency
- Supporting sourceRecent Activities for the New Chemicals Program under the Toxic Substances Control Act (opens in a new tab)U.S. Environmental Protection Agency