Visual overview — matching reprocessing to the exam, built on a cleaning-first foundation
Ultrasound probe reprocessing by Spaulding classification Three reprocessing levels for ultrasound transducers — non-critical, semi-critical, and critical — all built on a shared foundation of cleaning first, correct contact time, and hand hygiene. MATCH REPROCESSING TO THE EXAM The Spaulding classification, applied to ultrasound transducers NON-CRITICAL · contacts intact skin Transabdominal and most surface probes. Required: clean, then low-level disinfection EPA-registered agent, compatible with the transducer SEMI-CRITICAL · mucous membranes / non-intact skin Transvaginal, transrectal, probes on broken skin. Required: clean, then high-level disinfection FDA-cleared HLD agent, labeled concentration and dwell time CRITICAL · enters sterile tissue Intraoperative and sterile-field probes. Required: clean, then sterilize — sterile cover + sterile gel FOUNDATION FOR ALL THREE Clean first · correct contact time · hand hygiene

Ultrasound looks clean. That is the problem.

Most people picture ultrasound as one of the cleanest things in medicine. No needles, no incisions, just a probe gliding over skin. That picture is exactly why reprocessing gets rushed: a quick wipe, a fresh patient, next room. The reality is that a transducer touches patient after patient, often through nothing more than a thin film of gel, and the rules for cleaning it are not the same for every exam.

The Society for Maternal-Fetal Medicine (SMFM) tackled that confusion head-on in its updated 2026 special statement, Reducing the Risk of Transmitting Infection During Ultrasound Examination. It was written with obstetric imaging in mind, but the framework it uses is the one every ultrasound user should already be working from.

The rule underneath every other rule

Cleaning and disinfection are two different jobs. Cleaning removes gel, skin cells, and debris. Disinfection kills what is left. Disinfection does not work reliably until cleaning is done first, because leftover soil physically shields organisms from the disinfectant.

On every probe, after every patient, both steps happen — in that order. There are no exceptions to this part, regardless of which exam you ran.

3 Reprocessing levels, set by how the probe is used
2 Steps on every probe, every patient: clean, then disinfect
8–81% Reported failure range for some commercial probe covers
1–2% Leakage seen when condoms are used as endovaginal covers

Match the level to the exam

The statement organizes everything around the Spaulding classification — the same framework the CDC uses for every reusable medical device. The level of reprocessing a probe needs depends entirely on what the probe contacts.

Non-critical — transabdominal and surface probes

A probe that only ever touches intact skin is non-critical. After cleaning, it needs low-level disinfection — SMFM points to EPA-registered agents such as quaternary ammonium or phenolic products, always chosen for compatibility with the transducer. This is the largest share of day-to-day scanning in most practices, and it is also where corners get cut, because the risk feels low and the pace is high.

Semi-critical — endocavitary probes and non-intact skin

Transvaginal, transrectal, and any probe used over broken skin fall into the semi-critical tier. A cover plus a surface wipe does not meet the bar here. These probes require high-level disinfection with an FDA-cleared high-level disinfectant, used at the concentration and contact time the manufacturer specifies. SMFM also notes that common agents vary in their activity against HPV — one more reason to follow validated, labeled HLD rather than improvising.

Critical — intraoperative and sterile-field probes

A probe that enters sterile tissue is critical: clean, then sterilize, with a sterile cover, sterile gel, and strict aseptic technique. Fewer practices do this routinely, but when it applies, nothing lower will do.

"The fact that a probe looks clean, or was covered, tells you nothing about whether it was reprocessed to the level the exam required."

Covers help. They do not replace disinfection.

The statement is pointed about transducer covers: they are a barrier, not a substitute for reprocessing, and they fail more often than people assume. SMFM cites reported failure rates for some commercial covers ranging from 8% to 81%, with a well-run 2020 study of 500 covers reporting 0% to 5%. Condoms used on endovaginal probes showed roughly 1% to 2% leakage. The takeaway is not "stop using covers" — use FDA-cleared viral-barrier covers for intravaginal and intrarectal exams, and sterile covers for procedures. The takeaway is that you still disinfect to the correct level afterward, because the cover may not have held.

Gel is part of infection control, not an afterthought

Gel often gets treated as a simple consumable, but the statement puts it squarely inside the reprocessing conversation. The rules track the same tiers:

Non-critical exams: multi-use gel containers are acceptable — but discard them when empty and never top off or refill a bottle, which is a known route to contamination.
Semi-critical and procedural exams: use single-use gel, sterile where indicated, inside and outside the cover.
Ultrasound-guided percutaneous procedures: the CDC advises only single-use gel labeled sterile. A product labeled "bacteriostatic" or "preservative" is not sterile unless the label also says sterile.

A clean between-patient routine you can run

Between-patient reprocessing — step by step
1
Remove the cover and all gelWipe the transducer until there is no visible gel or debris. This is the cleaning step, and everything after it depends on it.
2
Disinfect to the right levelLow-level for intact-skin probes, high-level for endocavitary and non-intact-skin probes, sterilization for sterile-field use — always with a product compatible with your transducer's instructions for use.
3
Respect the contact timeLow-level or high-level, the disinfectant only works if it stays wet on the surface for the full labeled dwell time. For HLD, monitor solution concentration per the manufacturer before each use.
4
Handle gel by tierMulti-use bottles only for non-critical exams; single-use sterile packets for procedures. Never refill a container.
5
Hand hygiene, every timeBefore and after patient contact, even when gloves were worn — gloves are not fully leak-proof.
6
Make it auditableAssign ownership, train staff, and document reprocessing so compliance is something you can show, not just assume.
Alcohol is not a shortcut

Isopropyl alcohol has limited activity against some viruses and can degrade transducer housings and lenses over time. SMFM flags its weak virucidal activity against HPV specifically.

For routine probe and equipment cleaning, an alcohol-free, EPA-registered formulation validated as transducer-safe protects both the patient and the probe.

Where SONO fits — at each level, not just one

The reason this statement is worth building a routine around is that it is specific: it tells you which level applies and why. SONO's line is built the same way, so each tier has a tool that matches it.

Matching the product to the Spaulding level

SONO Ultrasound Disinfecting Wipes are an alcohol-free, EPA-registered, hospital-grade product developed through decades of work in the ultrasound and medical imaging industry (EPA Reg. #6836-340-89018). They are made for the cleaning and low-level disinfection step on transabdominal and surface probes — without the alcohol that damages transducer housings.

They are not a high-level disinfectant, and they do not replace HLD on endocavitary probes. For that tier, SONO is an authorized distributor of STERIS RESERT Revital-Ox. Matching the product to the level — rather than using one thing for everything — is the entire point of the guidance.

Non-critical · clean + low-level
SONO Ultrasound Disinfecting Wipes Alcohol-free, hospital-grade, formulated for ultrasound machines and transducers. No bleach, no harsh solvents. Made in the USA. For the clean-and-low-level step on intact-skin probes. EPA Registered
Semi-critical · high-level
STERIS RESERT Revital-Ox HLD Hydrogen peroxide high-level disinfectant for endocavitary probes, with R60 test strips to verify the solution is still at strength before use. SONO is an authorized STERIS distributor. FDA-Cleared HLD
Procedures · gel by tier
Clear Image Sterile Ultrasound Gel Sterile, single-use packets for ultrasound-guided procedures, where CDC advises gel labeled sterile. SONO scanning gel covers routine non-critical exams. Sterile · Single-Use
Build your reprocessing shelf by tier

One source for every level of ultrasound reprocessing

The clean-and-low-level step, the high-level disinfection step, and tier-correct gel — made in the USA, alcohol-free where it counts, and sized for clinics and veterinary practices.

Shop SONO Ultrasound Wipes
Scanning endocavitary probes?

High-level disinfection is required. See STERIS RESERT Revital-Ox HLD and R60 concentration test strips.

Shop High-Level Disinfection

The bottom line

The 2026 SMFM statement does not ask anyone to work harder. It asks them to work to the right level: clean every probe, every time; disinfect to what the exam actually requires; treat covers and gel as part of infection control rather than extras; and keep records that prove it. Done that way, reprocessing stops being the step that gets rushed and becomes the quiet reason your patients stay safe.

— ⋅ ⋅ ⋅ —

References & Sources

  • Society for Maternal-Fetal Medicine. Special Statement: Reducing the Risk of Transmitting Infection During Ultrasound Examination — Updated 2026. pubmed.ncbi.nlm.nih.gov · Full statement (PDF)
  • U.S. Centers for Disease Control and Prevention. A Rational Approach to Disinfection and Sterilization (Spaulding classification). cdc.gov
  • U.S. Food and Drug Administration. Reprocessing of Reusable Medical Devices; FDA-cleared high-level disinfectants. fda.gov
  • SONO Healthcare. SONO Ultrasound Disinfecting Wipes — EPA Reg. #6836-340-89018. sonowipes.com