---
title: IVDR Device Classification: The New Risk-Based System
description: IVDR device classification uses a four-class system (A, B, C, D) driven by the diagnostic target and substances. A startup-friendly walkthrough.
authors: Tibor Zechmeister, Felix Lenhard
category: IVDR & In Vitro Diagnostics
primary_keyword: IVDR device classification
canonical_url: https://zechmeister-solutions.com/en/blog/ivdr-classification-system
source: zechmeister-solutions.com
license: All rights reserved. Content may be cited with attribution and a link to the canonical URL.
---

# IVDR Device Classification: The New Risk-Based System

*By Tibor Zechmeister (EU MDR Expert, Notified Body Lead Auditor) and Felix Lenhard.*

> **The IVDR classifies in vitro diagnostic devices into four risk-based classes, from Class A (lowest risk) to Class D (highest risk). Classification depends on the diagnostic target, the substances detected, and the intended use. Unlike the old IVDD (where most devices were self-declared), the IVDR pushes the majority of modern diagnostics into notified body territory.**

**By Tibor Zechmeister and Felix Lenhard.**

## TL;DR
- The IVDR uses a four-class risk-based system: Class A, Class B, Class C, and Class D.
- Class A is the lowest risk and includes general laboratory products, specimen receptacles, and instruments intended for general laboratory use.
- Class D is the highest risk and covers devices intended to detect the presence of transmissible agents in blood, blood components, cells, tissues, or organs, and similar highest-risk diagnostic purposes.
- The classification rules are fewer and more compact than the MDR's 22 rules in Annex VIII, because the IVDR is built around diagnostic target and substances rather than invasiveness and duration.
- Only Class A (non-sterile) can be self-declared by the manufacturer. Class A (sterile), Class B, Class C, and Class D all require notified body involvement in some form.
- The classification decision is the regulatory hinge for the whole project. Budget, timeline, evidence scope, and notified body strategy all flow from it.
- Classification under the IVDR was the biggest shock to the industry when the regulation became applicable on 26 May 2022, because most devices that were self-declared under the IVDD moved up. 

## Why this matters (Hook)

Tibor has seen founders arrive at their first serious regulatory conversation with a classification assumption baked into the business plan. The assumption usually comes from a prior discussion with someone who had experience under the old IVDD and who remembers the world where most IVDs were Annex II self-declared. That world ended on 26 May 2022.

Under the IVDR, classification is the first domino. It determines which conformity assessment route applies, whether a notified body must be engaged, how much performance evaluation evidence is required, how the QMS will be audited, and how much the whole project will cost. Getting it wrong at the planning stage is not a detail mistake. It is a budget mistake, a timeline mistake, and in some cases a business model mistake.

Felix has coached diagnostics founders who discovered, at month ten, that their device was not Class B but Class C. The financial impact was measured in quarters of runway. The methodology lesson is simple: classify first, build second.

## What the regulation actually says (Surface)

Regulation (EU) 2017/746 sets out classification in a dedicated chapter and annex. Classification is based on risk rules that look at the intended purpose of the device, the diagnostic target, the medical decision informed by the result, and the nature of the substances analysed. 

The four classes:

- **Class A** covers the lowest risk devices. Examples in the regulation's intent include general laboratory products with no critical characteristics, specimen receptacles, and instruments intended for general laboratory use. Class A non-sterile devices can be self-declared by the manufacturer. Class A sterile devices require notified body involvement limited to aspects of sterility. 
- **Class B** covers moderate-risk devices that do not fall into A, C, or D. This includes many routine diagnostic products where the result informs non-critical clinical decisions. Class B requires notified body involvement. 
- **Class C** covers higher-risk devices, typically those informing important clinical decisions, including many infectious disease tests, companion diagnostics, and devices used to monitor critical analytes. Class C requires full notified body involvement. 
- **Class D** covers the highest-risk devices, including those intended to detect the presence of transmissible agents in blood, blood components, cells, tissues, or organs, used for transfusion or transplantation, and similar life-critical diagnostic purposes. Class D involves the most stringent oversight, including EU reference laboratory involvement in some cases. 

Tibor's one-line framing from his second follow-up interview: "Classification focuses on diagnostic target and substances. Fewer rules than MDR." The IVDR uses a smaller set of classification rules than the MDR's 22 rules in Annex VIII. Those rules are listed in the IVDR's classification annex and should be read directly, not summarised from memory.

The MDR comparison is instructive. Under the MDR, classification asks whether the device is invasive, whether it is active, how long it contacts the body, and how much energy it delivers. Under the IVDR, classification asks what you are detecting, whose decisions the result drives, and whether the substance or target is life-critical. Two completely different mental models.

## A worked example (Test)

Consider three real startup scenarios, walked through the IVDR classification logic.

**Scenario 1: A specimen collection tube with preservation buffer.**
A simple plastic tube containing a preservative for saliva samples, used to stabilise the sample for downstream testing. No active components, no diagnostic claim by the tube itself. This is consistent with Class A treatment as a specimen receptacle. If sold non-sterile, it can likely be self-declared. If sold sterile, notified body involvement is required for the sterility aspects. 

**Scenario 2: A rapid lateral-flow test for detecting a respiratory virus.**
A home-use rapid antigen test for a transmissible respiratory virus, with smartphone-based result reading. The detection target is a transmissible agent. The intended user is a layperson performing a self-test. Both factors push classification upward. In Tibor's experience, devices in this category typically land in Class C, and in specific cases involving high-risk transmissible agents, potentially Class D. The classification must be justified rule by rule in the documentation. 

**Scenario 3: A molecular assay for hepatitis B detection in donor blood.**
A nucleic acid amplification test used in blood bank settings to screen donor blood for hepatitis B. This is exactly the type of device Class D was designed for: detection of a transmissible agent in blood used for transfusion. Class D is the expected classification. 

The Subtract to Ship move across all three scenarios is the same: write a one-paragraph intended purpose, identify the diagnostic target, identify the user, identify the decision the result informs, then walk through the IVDR classification rules in order. Document the reasoning. Defend the decision to the notified body later.

Felix has seen teams try to "optimise" the intended purpose to get a lower class. This is a trap. Notified bodies see through it quickly, and the downstream consequence is a reclassification during the assessment, which costs time and money. Classification honesty is classification efficiency.

## The Subtract to Ship playbook (Ship)

1. **Write the intended purpose first.** One paragraph, plain language. Every classification decision flows from this statement.
2. **Identify the diagnostic target.** Is it a transmissible agent, a genetic marker, an analyte level, a companion diagnostic marker, or general laboratory output?
3. **Identify the user and the setting.** Is this a professional use device, a self-test, or a point-of-care test?
4. **Walk through the IVDR classification rules in order.** Do not skip. Document each rule that was considered and the decision reasoning.
5. **Reach the class.** A, B, C, or D. Write the justification as a standalone document.
6. **Map the conformity assessment route.** The class drives the route. Class A (non-sterile) can be self-declared. Every other class involves a notified body.
7. **Check for special categories.** Companion diagnostics, self-tests, near-patient tests, and devices for novel analytes may have specific provisions. Read the regulation, not a summary. 
8. **Have the justification reviewed.** By someone who has defended an IVDR classification to a notified body, not by someone who has read a blog post about it.

Felix's Subtract to Ship rule applies directly: the founder's job is to narrow. A clean, honest, well-justified classification is a subtraction of future ambiguity. It protects the business plan from surprises during the notified body audit.

## Reality Check

1. Can the team state the device's intended purpose in one paragraph of plain language?
2. Has the team identified the diagnostic target in precise terms (analyte, marker, agent)?
3. Has the team identified the intended user and the intended use environment?
4. Has the team walked through the IVDR classification rules in order and documented the reasoning?
5. Does the team know which class the device falls into, and can it defend the decision with reference to specific rules?
6. Does the team understand the difference between Class A non-sterile (self-declared) and all other classes (notified body involvement)?
7. Has the team checked whether the device is a companion diagnostic, self-test, or near-patient test (all of which can change the route)?
8. Has the team budgeted the conformity assessment route that the classification implies?

Fewer than six yes answers means the classification is not yet ready to drive planning decisions.

## Frequently Asked Questions

**How many classification rules does the IVDR have?**
The IVDR has a compact set of classification rules, fewer than the MDR's 22 rules in Annex VIII. The exact number and structure are defined in the IVDR classification annex. 

**Is Class A the same as Class I under the MDR?**
No. The labels look similar but the logic is different. MDR Class I is a risk-based medical device class. IVDR Class A is a risk-based IVD class built around specimen handling, general laboratory products, and instruments. Do not map one to the other.

**Can we self-declare a Class A device?**
Class A non-sterile devices can be self-declared by the manufacturer under the IVDR. Class A sterile devices require notified body involvement limited to sterility aspects. Every other class requires notified body involvement.

**What makes a device Class D?**
Class D generally covers devices intended to detect the presence of transmissible agents in blood, blood components, cells, tissues, or organs used for transfusion or transplantation, and similar life-critical diagnostic purposes. The classification annex defines the exact criteria. 

**Does a companion diagnostic have a specific class?**
Companion diagnostics typically fall into the higher IVDR classes because they inform specific therapeutic decisions. In many cases this means Class C. Read the classification rules against the specific device's intended purpose rather than assuming.

**Can our classification change during development?**
Yes. If the intended purpose evolves (new target population, new analytes, new decision informed by the result), the classification may change. The documentation must be updated and the notified body engagement re-scoped accordingly.

## Related reading
- [What is the IVDR? A startup guide](/blog/what-is-ivdr-startup-guide) is the foundational primer for teams new to the regulation.
- [IVDR vs MDR differences](/blog/ivdr-vs-mdr-differences) explains why classification is the biggest structural divergence between the two regulations.
- [MDR device classification explained](/blog/mdr-device-classification-explained) walks through the MDR classification logic, useful as a contrast.
- [What is a notified body?](/blog/what-is-notified-body) covers the role a body plays in the classes where self-declaration is not permitted.

## Sources
1. Regulation (EU) 2017/746 of the European Parliament and of the Council of 5 April 2017 on in vitro diagnostic medical devices, including classification annex.
2. Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices, Annex VIII for comparison.
3. EN ISO 13485:2016+A11:2021, Medical devices, Quality management systems.
4. EN ISO 14971:2019+A11:2021, Medical devices, Application of risk management.

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*This post is part of the [IVDR & In Vitro Diagnostics](https://zechmeister-solutions.com/en/blog/category/ivdr) cluster in the [Subtract to Ship: MDR Blog](https://zechmeister-solutions.com/en/blog). For EU MDR certification consulting, see [zechmeister-solutions.com](https://zechmeister-solutions.com).*