MDR Class IIa versus IIb: Why classification does not reflect disinfection quality

Competitors have recently used MDR Class IIa vs. IIb to claim UV-C disinfectors are “less validated,” but this reflects a misunderstanding of the MDR. MDR classification is based on risk, not performance, and Rule 16 clearly places UV-C disinfectors in Class IIa. This article explains why UV Smart’s classification is correct and why IIb does not indicate superior efficacy.

In recent months, some competitors have started using MDR Class IIa vs. Class IIb as an argument to position UV-C disinfection systems as “less validated” or “lower performance.”

This is factually incorrect as it does and does not reflect how the EU Medical Device Regulation (MDR) categorizes disinfection devices.

It's an unfortunate tactic lesser products use in their sales strategy.

This article explains what MDR classification actually represents, how MDR Annex VIII, Rule16 applies to UV-C disinfectors, and why Class IIa is the appropriate category for UV Smart’s technology.

MDR class is a risk category, not a performance score

Under MDR Annex VIII, Rule 16, devices intended to disinfect non-critical or semi-critical medical devices are classified as Class IIa.

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The rule is clear, only two categories fall under Class IIb in this context:

· chemical disinfecting solutions, and

· washer disinfectors intended for invasive devices at the end of processing

This distinction exists because MDR classification is based on risk, invasiveness, and potential harm in the event of device failure, not performance. It does not measure microbial reduction, speed, workflow impact, traceability, sustainability, or staff safety.

Why UV Smart is correctly classified as MDR Class IIa

UV Smart’s UV-C systems disinfect semi-critical, channel-less, non-porous, non-lumened medical devices such as ultrasound probes, TEE probes, and similar instruments.

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These devices:

· Do not introduce fluids, chemicals, or heat into patients.

· Have no lumens

· Precisely fit the risk profile defined for Class IIa under Rule 16.

High performance does not push a device into IIb; MDR classification is not performance-driven.

Why some competitor systems are MDR Class IIb

Some disinfection systems fall under Class IIb because they present higher inherent risk, for example:

· chemical formulations that pose burn, inhalation, or skin-contact risks

· fluid pathways, high-temperature processes, or steam

· invasive lumens used at the end of reprocessing

· more complex failure modes associated with mechanical or chemical systems

Class IIb classification therefore reflects risk management requirements, not superior disinfection quality.

Additionally, some systems were not reclassified correctly during the transition from the Medical Device Directive (MDD) →MDR (2021), because they didn’t re-evaluate their risk classification after the transition.

The NEN UV-C standard aligns with MDR Class IIa

The NEN standard for UV-C covers disinfection of non-critical and semi-critical medical devices. That is exactly the risk category defined as IIa under MDR.

The standard confirms UV-C that is:

· Validated

· Repeatable

· Safe

· Sustainable

· Appropriate for non-critical and semi-critical devices

This directly supports MDR Rule 16classification as IIa.