The EPA's Proposed EtO Reconsideration: What March 2026 Actually Means for Device Manufacturers

On March 17, 2026, the U.S. Environmental Protection Agency published a proposed rule in the Federal Register — 91 FR 12700 — proposing to rescind the core emissions standards from its April 2024 NESHAP rule governing commercial EtO sterilization facilities. The proposal is the most significant regulatory reversal in medical device sterilization in two decades. Public comments are due May 1, 2026.

Understanding what this means — and what it does not mean — requires separating the regulatory mechanics of the proposed rule from the supply chain and business risk environment that the rule was always embedded in.

What the 2024 NESHAP Actually Required

The 2024 final rule — finalized on April 5, 2024, under the Biden administration — amended the National Emission Standards for Hazardous Air Pollutants governing the approximately 90 commercial sterilization facilities owned by roughly 50 companies that collectively sterilize an estimated 20 billion medical devices annually. EtO is used to sterilize approximately 50 percent of all medical devices in the U.S. each year — devices including pacemakers, catheters, syringes, surgical kits, and ventilators that cannot withstand steam sterilization or the ionizing radiation required for gamma irradiation.

The 2024 rule imposed three categories of requirements that drew immediate industry opposition. First, it added risk-based emission standards under CAA section 112(f)(2) — a second risk review that industry argued was both legally questionable and duplicative of the 2006 review that EPA had previously determined adequate. Second, it required continuous emission monitoring systems (CEMS) for aeration room vents — a compliance infrastructure investment that smaller facilities argued was technically infeasible on their compliance timelines. Third, it imposed a permanent total enclosure (PTE) requirement for certain emission sources. The combined compliance burden prompted the Biden administration itself to establish a presidential exemption process in January 2025, after facilities made clear they could not meet the required standards before compliance deadlines without risking shutdown.

What the March 2026 Proposed Rule Does

The Trump EPA's March 2026 proposal is a formal reconsideration of the 2024 rule under its rulemaking authority. The core proposal: rescind the section 112(f)(2) risk-based standards that provided the primary legal justification for the 2024 NESHAP's most stringent requirements. The EPA's stated legal position is that CAA section 112(f)(2) permits only one risk review per source category — the review conducted in 2006 — and that the 2024 rule's invocation of a second review was statutorily unauthorized.

The proposed amendments would also revise the new aeration room vent standards, amend compliance demonstration requirements to allow facilities to choose between parametric monitoring or periodic performance testing rather than CEMS, and rescind the permanent total enclosure requirement. EPA estimates the proposed rule would save approximately $630 million in costs over 20 years, or approximately $43 million annually.

The judicial challenges to the 2024 rule filed in June 2024 by both industry groups (the Ethylene Oxide Sterilization Association) and environmental organizations are currently held in abeyance while the EPA completes this reconsideration — the D.C. Circuit granted EPA's abeyance motion on April 1, 2025, though it denied EPA's request to remand the 2024 rule. The court has retained jurisdiction.

What This Is Not

The reconsideration is not a return to the pre-2024 regulatory environment.

Several structural facts have not changed and will not change because of the proposed reconsideration:

**EtO's carcinogen classification is unchanged.** EPA classified ethylene oxide as a human carcinogen in 2016, citing evidence of associations with leukemia, lymphoma, and breast cancer in occupationally exposed workers. That classification — embedded in the IRIS toxicity value — is the foundation for every subsequent emissions rulemaking and is not affected by the 2024 rule reconsideration. The reconsideration disputes the statutory authority for a second risk review, not the underlying toxicity determination.

**Capital investments made under the 2024 rule are not recoverable.** The facilities that invested in abatement infrastructure, CEMS installation, or operational modifications during the 2024 compliance window did not do so provisionally. Those investments are sunk. For manufacturers who purchase contract sterilization services, the per-unit pricing that reflects those capital costs does not reverse because the rule that drove them is being reconsidered.

**Community opposition to EtO permitting continues.** The 2024 rule was partly a regulatory response to litigation and community activism around EtO facilities in Illinois, Georgia, and elsewhere. That activism is not dependent on the federal rulemaking framework and is not diminished by the proposed reconsideration. New EtO facility permitting, and expansion of existing facilities, faces a community and political environment that the proposed federal rollback does not change at the state and local level.

**The occupational exposure liability has not been resolved.** Workplace EtO exposure litigation has produced significant settlements and verdicts. Nothing in the March 2026 proposed reconsideration addresses the occupational liability exposure for facilities that use EtO as their primary sterilization agent.

The Strategic Risk Frame

The standard industry response to the March 2026 proposed reconsideration has been relief — a sense that the most severe compliance pressure has been deferred. That response is understandable and not incorrect as far as it goes. The 2024 rule created genuine near-term operational risk for facilities that could not meet its requirements, and the reconsideration removes that immediate risk.

The more important question for device manufacturers who depend on contract EtO sterilization is not what the proposed rule does in the next 12 months. It is what the underlying structure of EtO regulatory risk looks like over a 5- to 10-year planning horizon.

The 2024 rule did not create the underlying EtO risk environment — it was a response to it. EtO has been classified as a human carcinogen since 2016. Community opposition to EtO facilities predates both the 2024 rule and the current administration. The judicial challenges to the 2024 rule were filed by both industry and environmental groups, which means the fundamental tension between supply chain dependency and public health concern is embedded in the litigation landscape regardless of how the executive rulemaking resolves.

Manufacturers evaluating the EtO environment solely through the lens of the 2026 proposed reconsideration are reading a single data point in a longer regulatory series. The trajectory of that series — from the 2016 carcinogen classification, to the 2024 tightened NESHAP, to the 2025 presidential exemption process, to the 2026 reconsideration, to whatever follows — is not linear in any direction. The reconsideration introduces a policy reversal; it does not introduce stability.

VHP as Operational Hedge, Not Replacement

The practical question for manufacturers in 2026 is not whether EtO will be eliminated from the sterilization landscape. It will not. The question is whether complete operational dependency on a single modality that carries known regulatory, community, occupational liability, and supply chain concentration risk is the appropriate architecture for a durable manufacturing program.

[FDA's January 2024 Category A reclassification of VHP](/insights/category-a-two-years-later) resolved the primary historical objection to VHP adoption: regulatory uncertainty in submission review. VHP is now recognized alongside steam, EtO, dry heat, and irradiation as an established sterilization method. ISO 22441:2022, recognized by FDA as a consensus standard, provides a complete and mature validation framework: process development, biological indicator qualification, IQ/OQ/PQ, and routine control.

For manufacturers whose device portfolios include heat-sensitive, moisture-sensitive, or residue-sensitive products — the categories where EtO has historically dominated — VHP is not a theoretical alternative. It is a validated, regulatory-pathway-cleared alternative with growing adoption infrastructure and a material compatibility profile that aligns with the product categories driving current development pipelines.

The "AND" model — maintaining validated EtO capacity alongside a deployed VHP capability — is the architecture that eliminates the binary dependency. It is not a hedge against EtO's disappearance. It is a hedge against the uncertainty that the March 2026 proposed reconsideration itself embodies: a regulatory environment that has moved from tighter to looser in a single administration cycle, with active litigation on both sides and a judicial record that has held the underlying rule in place while the reconsideration proceeds.

The Timeline That Matters

The proposed reconsideration entered a 45-day comment period after its March 17, 2026 publication, with comments due May 1, 2026. A virtual public hearing was held on April 1, 2026. EPA is expected to finalize the rule within the next year, though the timeline is subject to the comment record and potential further litigation.

What the comment period and litigation timeline mean operationally: the regulatory environment for commercial EtO sterilization will remain unsettled through at least mid-2027. The 2024 rule has not been rescinded — it remains in effect pending finalization of the proposed reconsideration. The judicial challenges remain in abeyance with the court retaining jurisdiction. The final regulatory posture of commercial EtO sterilization in the United States will not be resolved until the reconsideration is finalized and any resulting litigation is resolved.

For manufacturers planning sterilization capacity investments in the 2026–2028 window, that is the timeline that governs. Not the proposed reconsideration's relief from the 2024 compliance burden, but the multi-year horizon of continued regulatory uncertainty in both directions.

Frequently Asked Questions

**What exactly does "rescinding the 112(f)(2) standards" mean for EtO facilities?**

Section 112(f)(2) of the Clean Air Act requires EPA to set risk-based emission standards for hazardous air pollutants that remain above acceptable risk thresholds after technology-based standards are applied. The 2024 rule used this authority to impose additional emission reductions beyond what technology-based standards alone required. EPA's proposed reconsideration argues that 112(f)(2) permits only one risk review per source category, and that the 2024 rule's second review was legally unauthorized. Rescinding those risk-based standards would remove the most stringent requirements from the 2024 rule while leaving the underlying technology-based standards of the 2006 rule intact. The full proposed rule text and EPA's explanatory materials are publicly available.

**Does the proposed reconsideration change VHP's regulatory status?**

No. VHP's FDA Category A designation, established in January 2024, is independent of EPA's EtO rulemaking. The Category A designation is an FDA determination about sterilization method recognition for medical device submissions — it is not affected by EPA air quality rulemaking. VHP's regulatory standing is unchanged regardless of how the EtO reconsideration resolves.

**What is the practical difference between the 2024 rule and the pre-2024 environment for contract sterilizers?**

The 2024 rule added CEMS requirements, permanent total enclosure requirements, and risk-based emission standards that imposed capital and operational costs on facilities. Some of those investments were already made before the reconsideration was announced. The pre-2024 environment applied the technology-based standards from the 2006 rule, which required EtO controls but not at the 2024 rule's stringency level. If finalized as proposed, the reconsideration returns the regulatory baseline to approximately the 2006 framework — but the costs already incurred under the 2024 transition are not reversed.

**How should manufacturers with EtO-dependent supply chains think about the proposed reconsideration?**

As one data point in a longer regulatory series. The reconsideration reduces near-term compliance pressure. It does not change EtO's carcinogen classification, the occupational exposure liability landscape, the community opposition environment around facility permitting, or the supply chain concentration risk of dependence on a single modality. Manufacturers conducting sterilization method risk assessments for 5- to 10-year planning horizons should model the reconsideration as a reduction in regulatory velocity, not a structural change in direction.

**What VHP validation steps are required before a manufacturer can use VHP in a 510(k) submission?**

VHP sterilization for 510(k) submission requires a validated process per ISO 22441:2022 — including process development (cycle parameter optimization), equipment qualification (IQ/OQ), performance qualification (PQ) with biological indicator data achieving SAL 10⁻⁶, material and packaging compatibility assessment, residue testing (ISO 21396), and routine control documentation. As an FDA-recognized Established Category A method, the submission does not require justification of VHP as an acceptable method — only documentation of the validated process. For manufacturers beginning from a clean slate, [6–12 months is a realistic timeline](/insights/category-a-two-years-later) from equipment procurement to a submission-ready validation package.

**Is the judicial abeyance the same as the 2024 rule being vacated?**

No. Abeyance means the litigation is paused, not resolved. The D.C. Circuit granted EPA's motion to hold the case while the agency completes its reconsideration, but explicitly denied EPA's request to remand the rule. The 2024 rule remains legally in effect during the abeyance period. The court has retained jurisdiction and will resume its review once the reconsideration rulemaking is complete. Whether the proposed reconsideration, if finalized, would moot the existing challenges or spawn new litigation from environmental petitioners is an open question the court has not resolved.