Understanding Harmonized Standards for medical devices and IVDs

Harmonized Standards are the preferred approach to demonstrate conformity of medical devices and their related processes with the applicable requirements in Annex I of the EU MDR and IVDR. However, many recognized international standards of high importance to medical device processes are still not harmonized under the EU MDR and IVDR. Other official references are also of importance and the manufacturer needs to understand when to use them. If you are unclear about the purpose and use of Harmonized Standards, read on.

Key takeaways

  • Harmonized standards are the basis to demonstrate conformity with the General Safety and Performance Requirements for medical devices and IVDs. The manufacturer may choose other methods but then needs to justify such choice.
  • Given the delays in harmonization of international standards under the EU MDR and IVDR, an approach to the use of ‘state-of-the-art ’ standards was introduced in guidance document MDCG 2021-5. This remains insufficient since non-harmonized standards do not confer presumption of conformity.
  • Common Specifications (CS), issued by the EU Commission in the form of Implementing Regulations, and monographs of the European Pharmacopoeia are other official references of the same category. Make sure you become familiar with these documents.


What are Harmonized Standards?

According to Article 2(1)(c) of Regulation (EU) No 1025/2012 on European standardization, a harmonized standard is a European standard adopted on the basis of a request made by the EU Commission for the application of EU harmonization legislation.

The purpose of a harmonized standard is to provide technical details and solutions to the safety and performance requirements that products placed on the European market must meet. The process of harmonizing a recognized international standard (typically ISO or IEC standards) in the EU involves establishing a relationship between the clauses in the standard and the requirements of the EU legislation that the standard is meant to cover. This relationship is described in the informative annexes “Z” (usually designated as Annex ZA, ZB, ZC,…) that are added to the harmonized version of the standard.

For medical devices (incl. in-vitro diagnostic devices), as stated in Article 8.1 of both IVDR (Reg. 2017/746) and EU MDR (Reg. 2017/745), following harmonized standards allows for the “presumption of conformity” with legal requirements applicable to the devices or their processes, like quality management systems, risks management, post-market surveillance, or clinical evaluation. The intention is to make device CE-marking (conformity assessment) an easier and quicker process. 

For more details on CE-marking of medical devices, see CE marking for in vitro diagnostic devices under the IVDR for in-vitro diagnostic devices (IVDs) and How to obtain a CE mark for a medical device for non-IVDs.

Examples of harmonized standards applicable for both EU MDR and IVDR:

  • EN ISO 13485:2016, Medical devices – Quality management systems – Requirements for regulatory purposes
  • EN ISO 15223-1:2021, Medical devices – Symbols to be used with information to be supplied by the manufacturer – Part 1: General requirements
  • EN ISO 14971:2019, Medical devices – Application of risk management to medical devices 

In addition, the monographs of the European Pharmacopoeia (PhEur), whose references have been published in the Official Journal of the European Union (OJEU), are covered under the concept of harmonized standards in the EU MDR and IVDR. This is particularly important for surgical sutures, for any medicinal products contained in medical devices, and for substance medical devices. Well-known pharmacopoeias from other jurisdictions (e.g. USP, JP) cannot be considered equivalent.

Switzerland and the United Kingdom (UK) present peculiarities due to the fact that their legislation is (to a greater or lesser extent) deviating from the EU MDR and IVDR and it is important to monitor how standardization might differ in these countries.

  • In the UK, because the medical device legislation in Great Britain is still based on the former EU Directives (note: the EU MDR and IVDR only apply in Northern Ireland), the standards harmonized under the EU MDR and IVDR would not be applicable in Great Britain. Moreover, the British Standardization Institute (BSI), responsible for adopting international standards in the UK, might generate British versions of the standards with a national annex that diverges from the Annex Z in the EU harmonized versions.
  • In Switzerland, for the time being there is no divergence in Swiss standards because the current Swiss legislation on medical devices (MedDO) and on in-vitro diagnostic devices (IvDO) are still based on the EU MDR and IVDR, respectively. This might change in the future. However, note that, in addition to the PhEur, the Pharmacopoeia Helvetica is also considered equivalent to harmonized standards in Switzerland.

Switzerland and the United Kingdom present peculiarities due to the fact that their legislation is deviating from the EU MDR and IVDR.

Are Harmonized Standards mandatory?

Contrary to popular belief, following harmonized standards is in fact voluntary. This is clearly stated both in guidance document MDCG 2021-5 Guidance on standardization for medical devices, and in Regulation (EU) No 1025/2012 on European standardization.

While following harmonized standards is voluntary, fulfilling the General Safety and Performance Requirements (GSPR) in Annex I of either the EU MDR or IVDR is not. The manufacturer is free to choose any methods to demonstrate conformity with the applicable GSPRs, and justify why the method is appropriate. In practice, not choosing a recognized harmonized standard means additional scrutiny from Notified Bodies and/or competent authorities, with sometimes interminable arguments about the validity of the chosen method. Therefore, following harmonized standards is generally considered to be the easiest and most efficient way to show product conformity with the requirements and achieve certification. 

Now, this is not quite the same for the monographs of the European Pharmacopoeia that are viewed as harmonized standards. If your devices are composed of, or integrate, a medicinal substance, you want to become familiar with the requirements of the corresponding monographs and with other relevant scientific guidelines issued by the EU Committee of Medicinal Products for Human use (CMPH).

Where can I find the standards harmonized under the EU MDR and IVDR?

The Official Journal of the European Union (OJEU) publishes references to all the harmonized standards by topic, including those for the EU MDR and IVDR, in the form of Commission Implementing Decisions. 

Unfortunately, only a handful of the international standards that used to be harmonized under the former EU Directives (MDD, AIMDD, and IVDD) are currently harmonized under the EU MDR and IVDR. Over 300 standards were harmonized under the former EU Directives, only 16 are harmonized under the EU MDR and 10 under the IVDR today. The frequency of harmonization is also very slow, with only 3 publications in the OJEU since July 2021, date of the first publication. The European standardization organizations have a considerable backlog of “candidate” standards to harmonize.

To access the latest version of the summary list of references, use the links below and scroll down to “Summary list as pdf document”:

Standards need to be purchased and this is best done via one of the 3 EU standardization agencies:

In addition, you can buy standards from the International Standards Organization (ISO) or from national standardization agencies. Note that national agencies sell the European standards (EN) in their national versions that, usually, do not differ at all from the EN version.

A full list of national standardization agencies can be found on the ISO members homepage. A selection is provided below.

The Estonian agency has a reputation for offering the standards at the lowest price, which is something you might want to consider when buying individual standards instead of as part of a package.

Most of the national standardization agencies provide a service that grants you access to your standards of interest digitally and keeps you posted on their status. These services can be more or less comprehensive and usually involve some discount for large numbers of standards.

How can I tell when a Harmonized Standard is obsolete?

Staying on top of when a Harmonized Standard becomes obsolete, for example due to its being replaced by an updated version, is challenging. The manufacturer needs to have a proactive regulatory intelligence program to monitor changes. Getting a subscription with one of the national agencies, as described in the previous section, is the most efficient approach but can be expensive. 

If you do not have a subscription that keeps you updated, the quickest way to verify the status of harmonized standards is to access the Summary List of Harmonized Standards for the relevant governing legislation:

If a harmonized standard has been withdrawn, this is noted in the table of the Summary List, where column (6) indicates the date when presumption of conformity ended and column (7) provides the reference to the Official Journal of the European Union.

The status of harmonized standards can also be checked on the websites of ISO or of the European and national standardization agencies.

If you are interested in a service that informs you about changes in harmonized standards, you can also contact Decomplix.

Staying on top of when a Harmonized Standard becomes obsolete, for example due to its being replaced by an updated version, is challenging.

Can I follow international standards that are not harmonized?

The short answer is yes. 

Given the slow pace in the harmonization of standards under the EU MDR and IVDR, a position on how to approach the presumption of conformity in the absence of harmonized standards had been insistently requested by the MedTech industry. This was intended to be achieved in guidance document MDCG 2021-5, which applied the concept of ‘state-of-the-art’ to recognized standards.

MDCG 2021-5 relies on multiple sources providing references, definitions and practical examples of ‘state-of-the-art’ (e.g.horizontal and vertical standards, guidance documents, agreements of working parties, European and international standards, sectorial papers,…) and refers to IMDRF, MDCG subgroup on standards, and MEDDEV 2.7/1 v4. 

In particular, the MDCG subgroup on standards is quoted as stating “The most recent editions of standard published by the standardizers should be considered as reflecting state-of-the art, regardless of OJ referencing”. This means specifically that if a standard exists in a previous harmonized version and in a new version that is not harmonized (not published in the Official Journal of the European Union) then the most recent version of the standard should be followed. 

Now, state-of-the-art standards do not confer presumption of conformity if no further evidence is provided in the technical documentation. Consequently, despite MDCG 2021-5, the issues due to missing harmonized standards under the EU MDR and IVDR remain unaddressed.

Are Common Specifications (CS) also Harmonized Standards?

Common specifications (CS) are not standards, harmonized or otherwise, although their purpose is basically the same: they consist of technical and/or clinical requirements that provide a means of complying with the legal obligations applicable to a device, process or system, per the definitions in EU MDR Art. 2(71) and IVDR Art. 2(74).

CS may be developed by the EU Commission where harmonized standards do not exist or are insufficient, or where there is a need to address public health concerns. They are published in the form of implementing regulations and can be found in the section “Implemented measures for regulations” of the EU Commission’s medical devices sector webpage on New Regulations. As such, they are free of charge.

The first CS published under the EU MDR concerned the reprocessing of single-use devices (Regulation (EU) 2020/1207) and the first one under the IVDR concerned certain Class D in-vitro diagnostic devices (Regulation (EU) 2022/1107).

The only other CS published to date concern products without an intended medical purpose governed by the EU MDR, as identified in EU MDR Art. 1(2). These products are similar to medical devices in terms of function and risk profile but only claim aesthetic or other non-medical purposes, and they are listed in EU MDR Annex XVI, thus commonly referred to as “Annex XVI products”. Product-specific CS allow these products to demonstrate conformity with the EU MDR even though they do not have an intended medical purpose. The CS for Annex XVI products were published in Implementing Regulation (EU) 2022/2346. For products that have both a non-medical purpose and a medical purpose, medical device requirements and Annex XVI product CS should be cumulatively fulfilled.

How Decomplix can help

Decomplix has extensive experience in helping companies determine the regulatory strategy for their medical devices and in-vitro diagnostic devices (IVD). 

Decomplix provides expert assessment of your situation and a complete roadmap to obtaining a CE mark for your IVD or your medical device. You can learn more about our services here.

If you are interested in a service that informs you about changes in harmonized standards, do not hesitate to contact Decomplix.

Further reading

More articles