Why Leading Sterilization Facilities Are Adding VHP to Their EtO Operations

Ethylene oxide sterilization is not going away. It sterilizes approximately half of all medical devices sold in the United States — more than 20 billion units annually — and despite years of regulatory pressure, the infrastructure that supports it remains deeply embedded in the medical supply chain. The EPA's March 2026 proposed reconsideration of its 2024 emission standards — which would relax, not tighten, the prior rule — confirms that EtO's role in the industry is more durable than many anticipated.

That durability is precisely why the most forward-thinking EtO facilities are adding VHP capability right now. Not because EtO is going away, but because a growing category of products cannot be optimally sterilized with EtO — and those products represent some of the fastest-growing segments in the medical device and life sciences markets.

The decision isn't EtO or VHP. It's EtO and VHP.

The Single-Technology Constraint

EtO is well-suited for a wide range of products: heat-sensitive devices, complex geometries, certain polymers, and densely packed product loads. It earned its dominant position through decades of validated performance across these applications.

What it is not suited for is an expanding class of products where residue, cycle time, or material sensitivity make EtO a poor fit. Combination products with drug coatings that degrade under EtO conditions. Cell therapy components where any trace of ethylene oxide residue is unacceptable. 3D-printed implants whose porous geometries trap residue and require extended aeration periods that change the economics of the process entirely.

These product categories are not niche. They are growing. And EtO facilities that cannot service them are turning away business — or watching manufacturers route those products elsewhere.

The Product Categories EtO Cannot Optimally Serve

The growth in biologics, advanced materials, and combination products is structural, not cyclical. Several specific categories represent concentrated opportunity for EtO facilities willing to add VHP capability:

Advanced biologics and cell therapy components — These materials require absolute zero residue. Ethylene oxide leaves trace residues that require extended aeration before product release, and published research has shown that EtO adducts with protein residues in biologics — including cysteine and methionine — even at residue levels within ISO limits. For cell-based therapies and biologics with residue-intolerant components, this is not a process constraint to be engineered around — it is a disqualifying characteristic.

3D-printed porous implants — The complex internal geometries created by additive manufacturing trap EtO gas in ways that complicate residue clearance and extend aeration requirements significantly. Research on sterilization of 3D-printed medical devices confirms that porous structures create extended desorption timelines that can compromise product release schedules. VHP, which decomposes completely to water and oxygen without requiring a separate aeration step, addresses this problem directly.

Combination products (drug + device) — Devices that incorporate pharmaceutical coatings, drug-eluting components, or biologics face material compatibility challenges with EtO that often cannot be resolved without compromising the drug component. Peer-reviewed studies on drug-eluting stent sterilization document measurable drug content loss attributable to the heat and humidity conditions of EtO cycles. The FDA's own guidance on combination product development notes that certain drug or biological product constituent parts may be altered or destroyed by terminal sterilization — a risk that must be assessed and resolved before regulatory submission.

Bioabsorbable implants requiring zero residue — For applications where implant-residue interaction is a concern — particularly in direct tissue contact applications — VHP's residue-free profile provides a technical advantage that simplifies both validation and regulatory submission.

These are not edge cases. They represent a meaningful and growing share of new product development pipelines in orthopedics, cardiovascular, regenerative medicine, and pharmaceutical combination products.

The "AND" Strategy

The framing of this decision matters. Adding VHP capability does not require retiring EtO capacity. It requires adding capacity — a second sterilization modality that handles product categories the first cannot.

The operational model is additive: EtO continues to process the product portfolio it serves well. VHP processes the categories where EtO is a poor fit. The facility gains the ability to serve a broader customer base, bid on product categories previously out of reach, and offer manufacturers a single-source solution for their entire device portfolio.

This is a revenue expansion story, not a cost reduction story. The EtO infrastructure is not redundant. It is complemented.

Consider the business case from the manufacturer's side: a device company developing a combination product cannot route that product through an EtO facility that cannot guarantee residue clearance or material compatibility. They will go elsewhere — to a contract sterilizer that offers VHP, or they will build the capability themselves. The EtO-only facility loses that customer permanently, not just for the current product but for every next-generation device in that manufacturer's pipeline.

The facilities adding VHP now are not hedging against EtO's decline. They are positioning to capture the product categories EtO cannot touch — categories that will represent a growing share of industry revenue over the next decade as the medical device pipeline shifts toward biologics, drug combinations, and advanced implant geometries.

The Regulatory Hedge

The March 2026 EPA proposed reconsideration is a useful data point, but it is not a stable equilibrium. The underlying tension between EtO's role in the medical device supply chain and its status as a known human carcinogen has not been resolved — it has been deferred. Regulatory direction has shifted multiple times over the past decade and will likely shift again.

The 2024 EPA final rule required more than 90% emission reductions. The 2026 reconsideration proposes to roll back portions of that standard. Neither outcome eliminates the underlying compliance obligation — the original 1994 NESHAP standards remain in place regardless of the reconsideration outcome, and community and legal pressure on EtO-intensive facilities has not diminished simply because the rulemaking pendulum has swung.

EtO facilities that have added VHP capability are not dependent on how that tension resolves. They have diversified their sterilization infrastructure in a way that reduces exposure to any single regulatory outcome. If future standards tighten, their VHP operations are already validated and running. If standards remain relaxed, their EtO operations continue unchanged.

The cost of building that optionality — adding a validated VHP system — is far lower than the cost of being forced to respond reactively to regulatory change. The facilities that add VHP under favorable conditions set the terms. Those that wait for regulatory pressure to force the decision will set the timeline on someone else's schedule.

SteriFlex: Designed for This Transition

PuroGen Laboratories has been developing and validating VHP sterilization systems since 1996. The SteriFlex platform — PuroGen's programmable VHP sterilization system — was designed from the beginning for the validation requirements of regulated industries: healthcare, medical devices, life sciences, tissue banking, and pharmaceutical manufacturing.

SteriFlex achieves SAL 10⁻⁶ terminal sterilization in cycles as short as 20 minutes. It operates with zero carbon footprint, leaves no residue (VHP decomposes to water and oxygen), and is non-destructive to the materials it processes. The system provides independent parametric control of VHP concentration, temperature, humidity, and cycle timing — allowing each product type to be validated against its specific material and packaging requirements without compromising the cycle parameters optimized for other products running through the same chamber.

That programmability is the operational key for multi-product facilities. A single SteriFlex system can run validated cycles for a bioabsorbable implant, a combination device, and a cell therapy component — each against its own validated parameter set, each with its own documentation trail. A fixed-cycle system cannot do this. The product diversity that characterizes modern contract sterilization demands programmable parametric control as a prerequisite, not a feature.

For EtO facilities evaluating VHP addition, SteriFlex is designed to operate alongside existing sterilization infrastructure. It does not require replacing what works. It requires adding what the current system cannot do.

The Strategic Window

The product categories that benefit most from VHP — advanced biologics, combination products, 3D-printed implants — are not waiting for sterilization infrastructure to catch up. They are entering development pipelines now, and the manufacturers behind them are making sterilization decisions that will determine which facilities they work with for the life of those products.

EtO facilities that have established validated VHP capability are in the conversation for those contracts. Those that have not are not. That gap will widen as the product pipeline matures, and the window to establish VHP capability on a deliberate timeline — rather than a reactive one — is open now, not indefinitely.

Frequently Asked Questions

**Can I add VHP sterilization to an existing EtO facility?**

Yes. VHP sterilization systems are modular and do not require dedicated facility infrastructure to the degree that EtO operations do. SteriFlex systems are designed to be commissioned within existing facility footprints, operating alongside EtO equipment without interference. The two processes are validated and operated independently.

**What is the difference between EtO and VHP sterilization?**

Ethylene oxide sterilizes through alkylation — a chemical reaction with microbial DNA and proteins. It requires post-sterilization aeration (typically 12–72 hours) to remove toxic residues before product release. Vaporized hydrogen peroxide sterilizes through oxidation and free-radical generation. It requires no aeration because VHP decomposes entirely to water and oxygen. Both methods achieve SAL 10⁻⁶ terminal sterilization, but their material compatibility profiles and residue characteristics differ significantly.

**How long does it take to validate a new VHP sterilization process?**

VHP process validation — including installation qualification (IQ), operational qualification (OQ), and performance qualification (PQ) — typically requires 6–12 months depending on product complexity and regulatory submission requirements. PuroGen's implementation support is designed to streamline this timeline, particularly for facilities with existing sterilization validation expertise.

**Is VHP sterilization recognized by the FDA?**

Yes. In January 2024, the FDA formally reclassified VHP sterilization to Established Category A — the designation for sterilization methods with a long history of safe and effective use on medical devices. This places VHP alongside steam, EtO, dry heat, and irradiation as a recognized terminal sterilization modality. ISO 22441:2022 provides the harmonized international standard for VHP process validation and aligns with FDA submission requirements.

**What products are best suited for VHP sterilization?**

VHP is particularly well-suited for products where residue is unacceptable, where materials are sensitive to EtO humidity and temperature conditions, or where complex geometries make EtO residue clearance difficult. This includes advanced biologics, combination products, 3D-printed implants with porous geometries, cell therapy components, and bioabsorbable materials with zero-residue requirements. For a detailed breakdown by product category, see our companion piece on the product categories EtO facilities cannot optimally sterilize.

**How does PuroGen support EtO facilities adding VHP capability?**

PuroGen's commercial model includes direct system deployment, private label manufacturing, and strategic collaboration — providing multiple pathways depending on facility scale, regulatory strategy, and commercial objectives. Implementation support includes process development, validation protocol design, IQ/OQ/PQ execution guidance, and regulatory documentation preparation. Contact PuroGen to discuss the appropriate model for your facility.