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General product and use information for laboratory, clinic and supply staff, not medical advice and not a processing procedure. Follow the sterilizer manufacturer’s instructions for use.
Short answer
Hydrogen peroxide gas plasma sterilization is a low-temperature method: hydrogen peroxide is vaporized in a vacuum chamber and energized into a plasma, and the cycle runs at about 37-44 °C. It is used for heat- and moisture-sensitive instruments. STERRAD is a brand of such sterilizers, not the name of the method itself (CDC, page dated 28 Nov 2023).
Definition and scope
CDC’s healthcare sterilization guideline says gas plasmas are generated “in an enclosed chamber under deep vacuum,” with radio frequency or microwave energy supplying the field. In the hydrogen peroxide version, the chamber is evacuated, hydrogen peroxide is vaporized, and the energy field creates the plasma. CDC states that microbicidal free radicals, such as hydroxyl and hydroperoxyl, are generated in the plasma.
The process is one of the low-temperature technologies CDC lists for items that cannot tolerate the heat and humidity of steam. CDC reports that the system has received FDA 510(k) clearance “with limited application” for sterilizing medical devices. “Limited application” is the reason to read the sterilizer’s own cleared claims before assuming a given device or lumen is supported. STERRAD systems and their cassettes are offered by Advanced Sterilization Products (ASP). This page explains the method generically rather than any one model.
How it works in practice
Three points from CDC describe what the process looks like to the people running it:
- Temperature: the process operates in the range of 37-44 °C, which is why heat-sensitive items are candidates for it.
- Dryness: “If any moisture is present on the objects the vacuum will not be achieved and the cycle aborts.”
- By-products: CDC says the by-products (water vapor, oxygen) are nontoxic and eliminate the need for aeration.
CDC also notes that the process has been compatible with most (more than 95%) of the medical devices and materials tested. That is a statement about tested materials, not a guarantee for any particular instrument.
Types and related concepts
Cycle time over generations of the system
| Version described by CDC | Cycle time |
|---|---|
| Original system | 75 minutes |
| Newer two-cycle version | 52 minutes (reduced from 73) |
| Newest version | 28-38 minutes |
Source: CDC, Hydrogen Peroxide Gas Plasma, dated 28 Nov 2023. ASP’s own cassette page states “complete sterilization in as little as 28 minutes” for its current cassettes, which is a manufacturer claim.
Gas plasma versus vaporized hydrogen peroxide
Both use hydrogen peroxide, but the plasma method adds an energy field that generates free radicals, as described above. On 8 January 2024 FDA announced that its revised final 510(k) sterility guidance lists vaporized hydrogen peroxide (VH2O2) as an example of an “Established Category A” sterilization method, citing its recognition of ISO 22441:2022. FDA’s announcement concerns vaporized hydrogen peroxide; it does not state that gas plasma systems moved category. For the broader comparison with ethylene oxide, VHP and ozone, see low-temperature sterilization method selection and VHP decontamination.
Where it matters for labs, clinics and supply decisions
FDA’s announcement states that ethylene oxide is the most commonly used sterilization method for medical devices in the U.S., and that FDA wants alternatives. That is the policy context in which hydrogen peroxide methods are discussed. A checklist for staff who work with these sterilizers, based on CDC’s description:
- Items must be dry. Moisture prevents the vacuum and aborts the cycle, so an aborted cycle is a prompt to look at dryness first.
- Lumens are a limiting factor. CDC says effectiveness can be altered by lumen length and diameter. Numeric limits belong to the sterilizer manufacturer’s validated device claims.
- The lumen diffusion enhancer is not cleared. CDC states the diffusion enhancer used outside the U.S. is not FDA cleared.
- Verification uses spores. The biological indicator CDC names for this system is Bacillus atrophaeus spores. For how indicators differ, see chemical indicators in sterilization.
- No aeration step is needed according to CDC, unlike ethylene oxide.
For other routes see sterilization technology, types of autoclaves for steam, and microwave sterilization.
Common misunderstandings
- “Sterrad” is the method. It is a brand of hydrogen peroxide gas plasma sterilizers.
- Gas plasma is microwave heating. The energy field generates reactive species at 37-44 °C; the process is not heat sterilization. See the microwave sterilization guide for the distinction.
- It works for any item. CDC reports FDA clearance “with limited application” and lumen effects; the device must be within the sterilizer’s cleared claims.
- It needs aeration like ethylene oxide. CDC says it does not.
FAQ
What is STERRAD?
A brand of low-temperature hydrogen peroxide gas plasma sterilizers from ASP, which lists cassette supplies for the STERRAD 100S, NX and 100NX systems.
Is gas plasma the same as VHP?
No. Both use hydrogen peroxide, but gas plasma adds an energy field that generates free radicals (CDC). FDA’s January 2024 category announcement is about vaporized hydrogen peroxide.
Does it need aeration?
CDC says the by-products are nontoxic and eliminate the need for aeration.
Why do cycles abort?
CDC states that if any moisture is present on the objects the vacuum will not be achieved and the cycle aborts.
Is it FDA cleared?
CDC reports FDA 510(k) clearance with limited application for sterilizing medical devices. The lumen diffusion enhancer used outside the U.S. is not FDA cleared.
Sources
- CDC, Hydrogen Peroxide Gas Plasma, Guideline for Disinfection and Sterilization in Healthcare Facilities (2008), page dated 28 Nov 2023; checked 30 Oct 2026.
- CDC, Sterilization, page dated 28 Nov 2023; checked 30 Oct 2026.
- FDA, FDA Facilitates Broader Adoption of Vaporized Hydrogen Peroxide for Medical Device Sterilization, 8 Jan 2024; checked 30 Oct 2026.
- ASP, STERRAD cassettes (manufacturer page); checked 30 Oct 2026.
