--- title: When an IFU Is Not Required Under MDR: Class I Exceptions description: Some Class I devices can be placed on the market without paper IFU under MDR Annex I Chapter III. Here is when the exception applies and what still must be communicated. authors: Tibor Zechmeister, Felix Lenhard category: Technical Documentation & Labeling primary_keyword: when IFU not required MDR canonical_url: https://zechmeister-solutions.com/en/blog/when-ifu-not-required-mdr source: zechmeister-solutions.com license: All rights reserved. Content may be cited with attribution and a link to the canonical URL. --- # When an IFU Is Not Required Under MDR: Class I Exceptions *By Tibor Zechmeister (EU MDR Expert, Notified Body Lead Auditor) and Felix Lenhard.* > **An IFU may be omitted under MDR only when the device can be used safely and as intended without any instructions for use. The legal anchor is Annex I Chapter III Section 23.1(d) of Regulation (EU) 2017/745, which allows the IFU to be left out for Class I and Class IIa devices where it is not needed for the device to be used safely and as intended. The exception is narrow, device-specific, and must be justified in the technical documentation on the basis of a risk analysis. Skipping the IFU is never a default; it is a documented regulatory decision that survives audit only if the justification is defensible.** **By Tibor Zechmeister and Felix Lenhard. Last updated 10 April 2026.** --- ## TL;DR - Annex I Chapter III Section 23.1(d) of Regulation (EU) 2017/745 allows an IFU to be omitted for Class I and Class IIa devices where it is not needed for the device to be used safely and as intended by the manufacturer. - The exception does not apply to Class IIb or Class III devices. For those classes, an IFU is always required. - Even when the IFU is omitted, the label obligations of Section 23.2 still apply in full, and the general principles of Section 23.1 still apply to whatever information does accompany the device. - Omitting the IFU must be justified in the technical documentation on the basis of a risk analysis. The justification is part of the file the Notified Body or competent authority will examine. - eIFU under Commission Implementing Regulation (EU) 2021/2226 is a different mechanism — it supplies the IFU in electronic form rather than omitting it. The two options should not be confused. - "No IFU" does not mean "no communication." The indication that the product is a medical device, the warnings at point of use, and the identification particulars all still have to reach the user through the label. --- ## Why founders ask this question The question comes up on every project with a very simple Class I device. A tongue depressor. A non-sterile bandage roll. A basic reusable instrument. The founder looks at the Section 23.4 list, sees twenty-plus mandatory items, imagines translating the document into every EU language, and asks the obvious question: does a device this simple really need a paper IFU at all? The honest answer is: sometimes no, and the Regulation has a specific provision for that case. The less honest answer — the one founders hope to hear — is that any simple device can skip the IFU. It cannot. The exception is narrow, the justification is real work, and the decision lives in the technical documentation for the Notified Body or competent authority to examine. This post walks through what the exception actually says, what it covers, what still has to reach the user when it applies, and what founders consistently get wrong about it. ## The general IFU obligation Section 23.4 of Annex I sets out the list of particulars that must appear in the instructions for use. For most devices, compliance with Section 23.4 means producing, validating, translating, and shipping a physical or electronic IFU that lists every required element. (Regulation (EU) 2017/745, Annex I, Chapter III, Section 23.4.) The default posture of the Regulation is that a medical device travels with an IFU. Section 23.1 — the general principles for information supplied with the device — sits above Section 23.4 and applies to every surface on which information reaches the user. Section 23.1 is where the exception lives. It is the only place in Chapter III where the Regulation contemplates that an IFU might not accompany a device at all. Every other part of Section 23 assumes an IFU exists. The full IFU walk-through for devices where the exception does not apply lives in [the dedicated IFU post](/blog/instructions-for-use-mdr-compliant). The rest of this post is about the narrow case where Section 23.1 allows the IFU to be omitted. ## The narrow exception: Section 23.1(d) Section 23.1(d) of Annex I Chapter III provides that instructions for use are not required for Class I and Class IIa devices if such devices can be used safely and as intended by the manufacturer without any such instructions for use. (Regulation (EU) 2017/745, Annex I, Chapter III, Section 23.1(d).) The exception has three parts, all of which must be satisfied before it can be relied on. **First, the device must be Class I or Class IIa.** A Class IIb or Class III device may never omit the IFU, regardless of how simple the device seems. The class cut-off is absolute. **Second, the device must be capable of being used safely without any instructions.** Safely is the operative word. If there is any residual risk that would be controlled by information-for-safety content in an IFU — any warning, any contraindication, any precaution — then the device cannot be used safely without the IFU, and the exception does not apply. The test runs through the ISO 14971 risk management file: if the risk controls for any residual risk include information for safety, the IFU is required. **Third, the device must be capable of being used as intended without any instructions.** As intended is the second operative phrase. If the user needs any instruction — on how to prepare the device, handle it, install it, clean it, dispose of it — in order to achieve the intended purpose, the exception does not apply. A device that the intended user can pick up and use correctly without guidance is a narrow category. All three parts must be satisfied together. Two out of three does not qualify. The manufacturer who wants to rely on the exception has to walk through each part and document the conclusion. ## What still must be communicated Omitting the IFU does not mean omitting the information supplied with the device. Section 23.2 — the label — still applies in full. Every label particular required by Section 23.2 still has to appear on the label or on the packaging, including the device identification, the manufacturer identification, the lot or serial number, the UDI carrier where the UDI obligation applies, the CE marking, the indication that the product is a medical device, storage or handling conditions where applicable, and any warnings or precautions that need to be at the immediate attention of the user at point of use. Section 23.1's general principles also still apply. The information that does accompany the device — on the label, on the packaging — must be in a form the intended user can understand, must be in the language required by each Member State under Article 10(11), and must use symbols from a recognised standard (in practice EN ISO 15223-1:2021) or describe any non-standard symbols in the documentation supplied with the device. The label-side walk-through is in [MDR labeling requirements](/blog/mdr-labeling-requirements), and the full Section 23 structure is in [MDR Annex I Chapter III: information supplied with the device](/blog/mdr-annex-i-chapter-iii-information-supplied). Both of those obligations survive the IFU omission. What changes is only that no separate IFU document is required — not that the communication obligation disappears. ## How to justify the omission The Section 23.1(d) exception is not self-executing. A manufacturer who wants to rely on it has to produce a documented justification that lives in the technical documentation and is available for Notified Body or competent authority review. The justification has the following elements. **A reasoned statement that the device is Class I or Class IIa**, referencing the applicable classification rule from Annex VIII and the classification analysis in the technical documentation. If the class is contested or borderline, the exception should not be claimed until the classification is stable. **A risk analysis conclusion that the device can be used safely without an IFU.** This comes out of the ISO 14971 risk management file. Every identified hazard and residual risk has to be examined against the question "does the safe control of this risk depend on information supplied to the user through an IFU?" If the answer is no for every residual risk, the first part of the safety test is satisfied. The risk file conclusion has to be explicit — not assumed, not inferred. An explicit statement that no residual risk is controlled by information-for-safety content that would require an IFU, signed off by the person responsible for risk management. **A use specification that shows the device can be used as intended without instructions.** This comes out of the usability engineering file under EN 62366-1:2015+A1:2020. The use specification defines the intended user, the intended use environment, the intended tasks, and the level of training and knowledge assumed. The justification demonstrates that a user meeting the use specification can accomplish the intended tasks safely and correctly without an IFU. Where usability validation has been performed, its results can support the justification. **A cross-reference to the label.** The justification should show that every element of Section 23.2 that applies to the device is present on the label or on the packaging, and that every warning or precaution the user needs at point of use is on the label itself — not relegated to an IFU that does not exist. **A positive statement that the exception of Section 23.1(d) is being relied on**, naming the subparagraph directly. This is the hook the Notified Body or competent authority will look for. A file that simply lacks an IFU without addressing why is a gap; a file that explicitly invokes Section 23.1(d) with a documented justification is a decision. ## What NOT to assume Several assumptions recur on every project where founders hope to skip the IFU, and each one is wrong. **"Our device is Class I so we do not need an IFU."** Class is a necessary condition, not a sufficient one. Most Class I devices still need an IFU because they cannot be used safely and as intended without instructions. Class I with a measuring function, Class I sterile, and Class I reusable surgical instruments all have characteristics that typically require some instruction content. **"Our device is obvious so the exception applies."** Obvious to the manufacturer is not the test. The test is whether the intended user, as defined in the use specification, can use the device safely and correctly without instructions. An engineer's sense of obviousness is not usability evidence. **"We will just put the IFU on the website."** Web-hosted IFUs are not an omission — they are an eIFU, governed by Commission Implementing Regulation (EU) 2021/2226 as amended. eIFU is a separate mechanism with its own conditions, its own risk assessment requirements, and its own eligible device categories. Treating "we do not ship paper" as equivalent to "we do not have an IFU" conflates two distinct regulatory routes and fails both. **"The exception covers Class IIb devices if they are simple."** It does not. Section 23.1(d) is limited to Class I and Class IIa. A simple Class IIb device still requires an IFU. **"Once we justify it, we can stop thinking about it."** The justification has to hold as the device evolves. A design change that introduces a new residual risk controlled by information for safety, a new user group that requires instruction, or a new intended use that cannot be inferred from the label all reopen the Section 23.1(d) analysis. The justification is a living document. ## Common mistakes - **Claiming the exception without documenting it.** The file has no IFU and also has no justification. At audit, this is a finding on both Section 23.4 (missing IFU) and Section 23.1 (no documented basis for the omission). - **Documenting a justification that does not address all three parts of the exception.** A file that argues class and safety but forgets the "used as intended" part is incomplete. - **Putting warnings only in an IFU that does not exist.** Warnings the user needs at point of use have to be on the label, not in a non-existent document. If Section 23.2's "warnings or precautions" subparagraph is being satisfied only through an IFU, then omitting the IFU is not an option. - **Confusing the exception with eIFU.** A manufacturer who says "we use the 23.1(d) exception and provide an eIFU on the website" is describing two contradictory routes. Pick one. - **Relying on the exception for a device that is about to be redesigned.** A change that introduces new tasks, new users, or new risks can reopen the analysis. Claiming the exception early and failing to re-examine it after a design change is how the gap appears. - **Assuming the Notified Body will agree without seeing the justification.** For Class IIa devices, the Notified Body reviews the technical documentation and will see the justification or its absence. For Class I self-certified devices, the competent authority can request the file at any time. In both cases, the justification has to be ready. ## The Subtract to Ship angle The Section 23.1(d) exception is, on its face, a subtraction opportunity. Removing the IFU from a project removes a multi-language translation burden, a usability validation step specific to the IFU, a document control obligation, and a revision pipeline that never ends. For the right device, the subtraction is real and substantial. The discipline of [the Subtract to Ship framework](/blog/subtract-to-ship-framework-mdr) applies in full here. The framework does not let you cut something just because you want to. It lets you cut something when you can defend the cut against a specific provision of the Regulation. Section 23.1(d) is the provision. The defence is the documented justification. Cut the IFU when you can defend it. Keep the IFU when you cannot. The default position for any non-trivial device is that the IFU stays, because the justification for omitting it will not hold. Subtraction on the IFU when the exception does not apply still has a place. A shorter IFU — one that contains every Section 23.4 required element and nothing more — is the normal subtraction move for the overwhelming majority of devices. The exception is the rare case where the subtraction goes all the way to zero. ## Reality Check — Where do you stand? 1. Is your device Class I or Class IIa, with the applicable Annex VIII rule documented in the technical file? 2. Does your ISO 14971 risk file contain an explicit statement that no residual risk is controlled by information-for-safety content that would require an IFU? 3. Does your use specification under EN 62366-1:2015+A1:2020 show that the intended user, with the assumed training and knowledge, can accomplish the intended tasks without instructions? 4. Does your label under Section 23.2 carry every warning and precaution the user needs at point of use — independent of any IFU? 5. Have you written a documented justification that explicitly invokes Annex I Chapter III Section 23.1(d) of Regulation (EU) 2017/745? 6. Have you confirmed you are not accidentally describing an eIFU as "no IFU" — i.e. you are not hosting instructions on a website and claiming the exception at the same time? 7. Do you have a process for re-examining the exception whenever the device is redesigned, the intended user changes, or a new residual risk appears? ## Frequently Asked Questions **Can a Class I medical device be sold without any IFU?** Only if Annex I Chapter III Section 23.1(d) applies — that is, only if the device can be used safely and as intended by the manufacturer without any instructions for use, and the manufacturer has documented that conclusion in the technical documentation. For most Class I devices the condition is not met. For the narrow cases where it is — truly simple devices with no residual risks requiring information-for-safety controls — the exception allows the IFU to be omitted. **Does the exception cover Class IIa devices?** Yes. Section 23.1(d) applies to both Class I and Class IIa devices that can be used safely and as intended without instructions. It does not apply to Class IIb or Class III devices under any circumstances. For Class IIa, the practical hurdle is higher because the Notified Body reviews the technical documentation and will scrutinise the justification for omitting the IFU. **Is "no IFU" the same as eIFU?** No. eIFU — electronic instructions for use under Commission Implementing Regulation (EU) 2021/2226 as amended — supplies the IFU in electronic form rather than on paper. The IFU still exists; it is just delivered differently. Section 23.1(d) is different: it allows the IFU to be omitted altogether for eligible devices. Mixing the two routes produces a file that is defensible under neither. **If the IFU is omitted, what about warnings?** Warnings the user needs at point of use have to be on the label. Section 23.2 requires "warnings or precautions that need to be brought to the immediate attention of the user of the device." When the IFU is omitted, every such warning has to be carried by the label (with support from Section 23.1(h) symbols where appropriate). If a warning cannot fit on the label and there is no IFU to carry it, the Section 23.1(d) exception cannot be relied on. **Where do I document the justification for omitting the IFU?** Inside the technical documentation, as part of the information-supplied-with-the-device section. The justification references Section 23.1(d) directly, sets out the class, draws on the risk management file and the usability use specification, and confirms that every applicable Section 23.2 element is present on the label. It should be signed off by the person responsible for regulatory compliance under Article 15. **Does the exception survive a device redesign?** Not automatically. Any design change that introduces a new residual risk controlled by information for safety, a new user group that needs instruction, or a new intended task that cannot be inferred from the label reopens the analysis. The justification has to be refreshed whenever the conditions that supported it change. ## Related reading - [Intended Purpose Under MDR Article 2(12)](/blog/intended-purpose-mdr-article-2-12) — the definition that determines what "used as intended" means for the exception. - [MDR Labeling Requirements: What Must Appear on Your Device Label](/blog/mdr-labeling-requirements) — the Section 23.2 obligations that survive the IFU omission. - [MDR Annex I Chapter III: Information Supplied with the Device](/blog/mdr-annex-i-chapter-iii-information-supplied) — the full Section 23 structure. - [The Instructions for Use (IFU) Under MDR: How to Write Compliant IFUs](/blog/instructions-for-use-mdr-compliant) — the companion post for devices where the IFU is required. - [The Implant Card Under MDR Article 18 and Section 23.3](/blog/mdr-implant-card-article-18) — why implantable devices are never candidates for the exception. - [Electronic Instructions for Use (eIFU) Under MDR](/blog/mdr-eifu-electronic-instructions) — the separate mechanism under Commission Implementing Regulation (EU) 2021/2226 as amended. - [Common Labelling Mistakes Startups Make Under MDR](/blog/common-labeling-mistakes-startups-mdr) — the recurring failure modes that connect to Chapter III. - [The Subtract to Ship Framework for MDR Compliance](/blog/subtract-to-ship-framework-mdr) — the methodology behind making a disciplined call on whether the exception applies. ## Sources 1. Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices, Annex I, Chapter III, Section 23.1 (general principles for information supplied with the device, including subparagraph (d) on the IFU exception for Class I and Class IIa devices), Section 23.4 (information in the instructions for use). Official Journal L 117, 5.5.2017. 2. Commission Implementing Regulation (EU) 2021/2226 of 14 December 2021 laying down rules for the application of Regulation (EU) 2017/745 as regards electronic instructions for use of medical devices, as amended by Commission Implementing Regulation (EU) 2025/1234 of 25 June 2025. --- *This post is part of the Technical Documentation & Labeling cluster in the Subtract to Ship: MDR blog. Authored by Felix Lenhard and Tibor Zechmeister. The Section 23.1(d) exception is real, and for the right device it is a substantial subtraction — but the default is that an IFU is required, and the file has to prove the exception applies before the IFU comes out.* --- *This post is part of the [Technical Documentation & Labeling](https://zechmeister-solutions.com/en/blog/category/technical-documentation) 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).*