Class Is · MDR Article 52(7) · Sterile barrier
Sterility adds more than a letter to Class I. It adds a controlled system
The device remains low risk. The process that makes it sterile and keeps it sterile until use is independently assessed.
The costly mistake is to treat sterilization as the last manufacturing step. For Class Is, sterility begins with device and packaging design, continues through validation and routine release, and remains under control throughout the post-market lifecycle.
Explore the Class Is route ↓sterile
The short answer
The manufacturer owns the whole device. The notified body assesses sterility
Class Is is not a new risk class. It is a Class I device that the manufacturer places on the market in a sterile condition.
Before affixing the CE marking, the manufacturer involves a notified body for the aspects concerned with establishing, securing and maintaining sterile conditions.
What actually changes
The same underlying classification, two different routes
Sterility does not turn the device into Class IIa. It changes the conformity assessment procedure for a Class I device.
Self-declaration route
The manufacturer completes conformity assessment without a notified body
After preparing the technical documentation under Annexes II and III, completing the clinical evaluation and demonstrating the applicable GSPR, the manufacturer draws up the EU declaration of conformity and affixes the CE marking.
- Technical documentation remains mandatory
- Clinical evaluation remains mandatory
- The Article 85 PMS report applies
Limited certification scope
The notified body enters the route before the declaration is issued
The manufacturer chooses the procedure under Annex IX, Chapters I and III, or Annex XI, Part A. The assessment is limited to the aspects concerned with establishing, securing and maintaining sterile conditions.
- A notified body agreement is required
- A certificate covering the applicable scope is required
- The notified body number appears beside the CE marking
The assessment boundary
A Class Is certificate is not an approval of the entire device
The limited scope of notified body involvement does not reduce the manufacturer’s obligations under the rest of the MDR.
The sterility assurance system
- The selected sterilization method and its suitability
- Process validation and product-family definition
- Microbiological control and bioburden
- The sterile barrier system and package integrity
- Routine monitoring, release and deviation management
- Maintenance of the validated state and change control
The complete device compliance case
- Intended purpose, qualification and classification
- Risk management and GSPR compliance
- Clinical evaluation and clinical claims
- Performance verification and biological safety
- Labelling, instructions for use and languages
- UDI, registration, PMS, PMCF and vigilance
The phrase “notified body certified” must not imply that the body approved the clinical claims or the entire technical documentation. The certificate scope should always be described precisely.
The sterility assurance chain
Sterility must survive manufacturing, transport and shelf life
Sterilization validation answers only part of the question. The user must receive a sterile device whose safety and performance have also been preserved.
- 01Requirement
Define the sterile condition
Specify which variants are supplied sterile, how they are used and which conditions must remain intact until the moment of use.
- 02Compatibility
Challenge the device and materials
Assess the effect of the process on materials, function, biocompatibility, medicinal substances, electronics and acceptable degradation.
- 03Process
Develop and validate the cycle
Define the load, worst case, critical parameters, acceptance criteria, routine monitoring and conditions for revalidation.
- 04Barrier
Protect the sterile condition
Validate package forming and sealing, barrier integrity, transport resistance, ageing and the ability to open the package aseptically.
- 05Release
Control every batch
Review process parameters, indicators, dosimetry or other records, deviations, packaging status and release authorization.
- 06Lifecycle
Maintain the validated state
Assess changes to the device, packaging, equipment, site, load and supplier, together with PMS signals and the need for revalidation.
A method is not chosen by habit
Every sterilization technology changes the evidence package
The choice should follow the design, materials, packaging, bioburden, manufacturing scale and acceptable residual risks. Select a method to see the questions it adds to the technical documentation.
Low-temperature process
Suitable for many sensitive materials, but it leaves chemical questions behind
The evidence usually covers cycle development and validation, microbiological effectiveness, aeration, residual EO and reaction products, material compatibility and packaging safety.
EN ISO 11135 · EN ISO 10993-7 · EN ISO 11737
Gamma radiation or electron beam
A clean routine process still demands a justified dose and stable materials
The critical evidence includes sterilization-dose establishment, dose mapping, microbiological justification, control of minimum and maximum dose, radiation stability of materials and the effects of ageing.
EN ISO 11137 · EN ISO 11737 · EN ISO 11607
Saturated steam
A robust physical method places strict demands on heat resistance
The manufacturer must demonstrate steam penetration, air removal, reproducible time and temperature, suitability of the load configuration, dryness after the cycle and preservation of device and packaging characteristics.
EN ISO 17665 · EN ISO 11737 · EN ISO 11607
Aseptic processing
When terminal sterilization is impossible, process control becomes harder
The case requires a strong justification for not using terminal sterilization, environmental and personnel controls, validation of aseptic operations, component sterilization, process simulations and contamination control.
EN ISO 13408 · EN ISO 14644 · applicable pharmacopoeial methods
The sterility dossier
The notified body needs to see a controlled system, not a folder of protocols
The documentation should explain why the process is suitable, how it was validated, how each batch is controlled and what happens when something changes.
Sterility strategy
Product-family boundaries, method rationale, target sterile condition, regulatory strategy and allocation of responsibilities.
FoundationRisk and compatibility
Effects of sterilization on function, materials, biocompatibility, packaging, residuals and use-related risks.
Device connectionProcess validation
Protocols, reports, worst case, critical parameters, acceptance criteria, equipment qualification and revalidation.
EvidenceSterile barrier
Material specifications, forming and sealing validation, integrity, transport, ageing and shelf life.
PreservationRoutine control
Production records, parameter monitoring, batch release, deviations, CAPA, maintenance and change control.
ReproducibilityPost-market data
Complaints involving packaging, non-sterility, damage or infection, together with trends, corrective action, PMS and risk updates.
LifecycleSterilization can be outsourced. Responsibility cannot.
An external sterilization facility becomes a critical supplier
The supplier operates the equipment and runs the cycle. The manufacturer defines the device requirements, approves the validation strategy, controls the data and remains responsible for the conformity of the released product.
ISO 13485 confirms a quality management system within its stated scope. It does not automatically prove that a particular cycle, load and package are suitable for your device.
Defines
Requirements, product families, worst case, acceptance criteria and release rules.
Executes
The qualified process, cycle monitoring, equipment control and agreed records.
Decides
Whether the batch is acceptable, whether a change is significant and whether the validated state is maintained.
From decision to market
The Class Is route consists of eight connected decisions
The sequence can be adapted to the project, but no block can simply be replaced by a supplier or notified body certificate.
- 01Qualification
Confirm the medical purpose
Define the product, variants, intended users and conditions of use.
- 02Classification
Justify Class I and the sterile condition
Apply the Annex VIII rules and clearly separate sterile variants from non-sterile variants.
- 03System
Build sterility into the QMS
Define processes, roles, suppliers, release, deviations, CAPA and change control.
- 04Evidence
Complete verification and validation
Connect the device, sterilization, biological safety, packaging and shelf life.
- 05Notified body
Complete the limited conformity assessment
Present the system and documentation relating to sterile conditions.
- 06Declaration and CE
Declare conformity and affix the marking
Once the applicable certificate is issued, draw up the declaration and place the notified body number beside the CE marking.
- 07EUDAMED
Register the actor and device
Use the actor, UDI/device and notified body/certificate modules that became mandatory on 28 May 2026.
- 08Post-market
Run PMS and maintain certification
Analyse signals, update the PMS report, risks and clinical evaluation, and control significant changes.
Where projects lose time
Seven mistakes that are usually discovered too late
Most delays do not begin inside the sterilizer. They begin where the boundaries between device, packaging, process and responsibility have not been aligned.
- 01
Treating Class Is as a separate risk class and failing to justify the underlying device classification under Annex VIII.
- 02
Selecting the sterilization method after design completion and discovering material or electronic incompatibility too late.
- 03
Validating the cycle without a defensible product-family rationale, worst case and load configuration.
- 04
Running sterilization and packaging as separate projects even though the sterile condition depends on both processes.
- 05
Relying on supplier certificates instead of securing access to validation, batch and change data for the actual process.
- 06
Failing to assess the effects of sterilization on biocompatibility, function, residuals and clinical performance.
- 07
Informing the notified body only after a change is implemented without first checking the agreement, certificate and change-control procedure.
Practical questions
Frequently asked questions about Class Is
Short answers are useful only when they do not conceal the boundaries of responsibility.
Is Class Is a separate risk class?+
No. The device remains a Class I device. The Is designation is commonly used to show that the device is placed on the market in a sterile condition and that a notified body must therefore assess the aspects relating to sterility.
Does the notified body review the entire technical documentation for a Class Is device?+
The mandatory scope of notified body involvement is limited to the aspects concerned with establishing, securing and maintaining sterile conditions. The manufacturer remains responsible for classification, clinical evaluation, risk management, GSPR compliance and the completeness of the technical documentation.
Can sterilization be outsourced?+
Yes. The manufacturer must still qualify the supplier, define the requirements, control changes, retain access to validation and routine processing data and demonstrate that the process remains effective. The manufacturer’s regulatory responsibility is not transferred to the supplier.
Is the sterilization supplier’s ISO 13485 certificate sufficient?+
No. A quality management system certificate is useful, but it does not replace validation of the specific process for the specific device, an agreed specification, load control, release criteria, deviation management and change control.
Which PMS report is required for a Class Is device?+
For a Class I device, the manufacturer prepares a PMS report under Article 85 MDR and updates it when necessary. The PSUR required for Classes IIa, IIb and III is not required for Class Is.
Primary sources
Check the route against the source
MDCG documents support the application of the MDR, but they do not replace the Regulation and are not legally binding.
Regulation (EU) 2017/745
Articles 20, 27, 29, 52, 61 and 83–85, together with Annexes II, III, IV, VIII, IX and XI
MDCG 2019-15 rev.1
Guidance notes for manufacturers of Class I medical devices
EUDAMED
Current status of mandatory module use from 28 May 2026
MDCG guidance
The current catalogue of guidance on classification, clinical evaluation, PMS and EUDAMED
From a sterile claim to a certified system
Preparing a Class Is device for notified body assessment?
MDRC can review the classification, define the certification scope, build the evidence strategy and prepare the sterilization, packaging, QMS and PMS documentation.
