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Short answer
VHP decontamination uses vaporized hydrogen peroxide to treat enclosed spaces, chambers and equipment surfaces. It is related to, but not the same as, VH2O2 sterilization of medical devices in a sterilizer. CDC describes atmospheric VHP systems for decontaminating large and small areas, and notes that room-fogging technologies fall outside its 2008 recommendations.
Definition and scope
VHP stands for vaporized hydrogen peroxide, also written VH2O2. The CDC/HICPAC Guideline for Disinfection and Sterilization in Healthcare Facilities notes that VHP was not developed for the sterilization of medical equipment until the mid-1980s, and lists two families of application: vacuum systems for industrial sterilization of medical devices, and atmospheric systems for decontaminating large and small areas.
That split is the most useful way to read the term. “VHP decontamination” in a lab or clinic usually means the second family: treating a room, enclosure or piece of equipment so that surfaces carry a lower microbial load. Sterilizing a packaged device inside a dedicated sterilizer is a different regulated activity (see the table below).
How VHP is delivered in practice
CDC describes two delivery approaches:
- Vacuum cartridge systems. A deep vacuum pulls liquid hydrogen peroxide (30-35% concentration) from a disposable cartridge through a heated vaporizer into the chamber.
- Flow-through systems. A carrier gas such as air moves the vapor through the space under slight negative or positive pressure.
CDC lists these features for the technology: rapid cycle time (for example 30-45 minutes), low temperature, environmentally safe by-products (water and oxygen), good material compatibility, and ease of operation, installation and monitoring. These are the features CDC attributes to the sterilization technology; they are not a promise for every room or enclosure.
In its 2024 update, CDC also notes that vapor-phase hydrogen peroxide was evaluated as a surface decontaminant and sterilizer in a centrifuge decontamination application and showed significant sporicidal activity, and that preliminary studies found hydrogen peroxide vapor decontamination highly effective against organisms such as MRSA and Serratia.
Decontamination versus sterilization: where the line sits
The table separates four situations that are often blurred. The sources are listed at the end.
| Situation | What the sources say |
|---|---|
| Sterilizing medical devices with VH2O2 | FDA considers VH2O2 an Established Category A sterilization process, after recognizing ISO 22441:2022 (low temperature vaporized hydrogen peroxide). This is a device-sterilization pathway, not a room-treatment one. |
| Decontaminating areas and chambers | CDC lists atmospheric VHP systems for decontaminating large and small areas as an application of the technology. |
| Fogging a room (including vaporized hydrogen peroxide) | CDC states its 2008 recommendations do not apply to newer room-fogging technologies, and that it does not yet make a recommendation regarding them; the 2011 norovirus guideline it cites lists the question as an unresolved issue requiring more research. |
| Biosafety cabinets | Gas decontamination is one of the options for cabinets; see our guide to biosafety cabinet cleaning and decontamination. |
For the device side, our guides on low-temperature sterilization method selection and sterilization technology cover VH2O2 sterilizers; this page does not repeat them.
Where it matters for labs and clinics
The practical consequence of the CDC position is a claims check. A supplier or protocol that says a VHP cycle “sterilizes a room” is describing something different from the FDA Category A pathway for sterilizers, and CDC itself makes no recommendation on room-fogging systems.
Three sourced checkpoints apply to any VHP process for equipment or an enclosure:
- Material list. CDC states that cellulose cannot be processed and nylon becomes brittle. Paper-based items and nylon components fall outside what the process can treat.
- Penetration. CDC states that VHP penetration capabilities are less than those of ethylene oxide. It also cites peer-reviewed publications raising concerns about low-temperature processes, VHP included, when organisms are challenged with serum and salt in narrow lumens. Items with narrow lumens and organic soil are the documented concern.
- Worker exposure. OSHA’s Annotated Table Z-1 lists a permissible exposure limit of 1 ppm for hydrogen peroxide.
Validation of any cycle follows the same logic as other sterility claims; see sterilization validation and the explainer on sterility assurance level. For routine surface work that does not need gas, surface disinfectant selection is the more usual route.
Common misunderstandings
“VHP and VH2O2 sterilization are the same thing.”
The agent is the same; the regulated use is not. FDA Category A status applies to sterilization of medical devices. Area decontamination is a separate application in CDC’s description.
“CDC recommends VHP room decontamination.”
CDC’s 2008 recommendations do not apply to room-fogging technologies such as vaporized hydrogen peroxide, and CDC does not yet make a recommendation on them.
“VHP reaches everything.”
CDC lists lower penetration than ethylene oxide and material restrictions (cellulose, nylon).
FAQ
What does VHP stand for?
Vaporized hydrogen peroxide, also written VH2O2.
What is VHP decontamination used for?
CDC lists atmospheric systems for decontaminating large and small areas, and a centrifuge decontamination application evaluated in its 2024 update.
Does VHP leave toxic residue?
CDC lists water and oxygen as the environmentally safe by-products of the technology. OSHA also lists a permissible exposure limit of 1 ppm for hydrogen peroxide in workplace air.
Can VHP process paper or nylon?
CDC lists these as limitations: cellulose cannot be processed and nylon becomes brittle.
Sources
- CDC / HICPAC, Guideline for Disinfection and Sterilization in Healthcare Facilities (2008, content updated June 2024), checked 2026-10-29: cdc.gov guideline PDF.
- U.S. FDA, Sterilization for Medical Devices, checked 2026-10-29: fda.gov.
- OSHA, Annotated PELs, Table Z-1, checked 2026-10-29: osha.gov.
