CE conformity assessment modules are the core operational framework of the CE marking system. Their key role is to define “through which procedure” a product demonstrates compliance with EU legislation, so that products of all risk levels can complete conformity assessment through a standardised route and be legally placed on the EU market.
Under Decision No 768/2008/EC, the conformity assessment procedures are divided into Modules A, B, C, D, E, F, G, H and others. For a detailed PDF of the decision, download it from the link below or reply “Module” to our WeChat account: https://www.everbiz.com.cn/ziliaoxiazai/
In the CE system, conformity assessment is completed either by “a single module” or by “a combination of modules”, depending on the product’s risk level.
(1) Modules commonly used on their own
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Module A – Internal production control
(Low risk, fully self-controlled)
Procedure: the manufacturer tests the product and assesses conformity itself, signs a self-declaration and affixes the CE marking. Applicable to: very low-risk simple products where the relevant EU directive allows self-declaration.
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Module A1 – Internal production control plus supervised product testing
(Low risk, periodic third-party verification)
Procedure: the manufacturer is responsible for day-to-day self-control and, at fixed intervals, commissions a laboratory (or notified body) to test product samples, keeping the test reports.
Applicable to: low-risk products that need some external verification (such as some simple electronic accessories), where the relevant directive requires periodic testing to support conformity.
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Module A2 – Internal production control plus supervised product checks at random intervals
(Low risk, unscheduled third-party spot checks)
Procedure: the manufacturer controls production itself, and the notified body (or its authorised body) carries out random product checks at irregular intervals to confirm continued conformity.
Applicable to: low-risk products that need “unpredictable oversight” (such as some standardised construction materials), using random checks to reduce compliance risk.
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Module D1 – Quality assurance of the production process
(Medium-low risk, focus on stable production)
Procedure: the manufacturer establishes a production quality system (similar to ISO 9001 but meeting the specifics of the EU directive), which the notified body audits and monitors to ensure a stable and compliant production process.
Applicable to: mass-produced products whose safety depends on process stability (such as automotive parts and industrial fasteners).
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Module E1 – Quality assurance of final product inspection and testing
(Medium-low risk, ensuring each item conforms)
Procedure: the manufacturer establishes a finished-product inspection process (such as full testing and visual checks), and the notified body monitors its effectiveness to ensure every product is inspected for conformity.
Applicable to: products where individual variation may affect safety (such as some medical consumables and small protective tools).
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Module F1 – Conformity based on product verification
(Medium-high risk, comprehensive third-party verification)
Procedure: the notified body fully tests the product (including design, performance and safety); only after conformity with the directive is confirmed may the manufacturer affix the CE marking.
Applicable to: medium-high-risk products requiring comprehensive third-party verification (such as new electronic equipment and non-standard machinery).
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Module G – Conformity based on unit verification
(Medium-low risk, sampling to cover a batch)
Procedure: the notified body selects “representative units” from a batch for testing; if they pass, the whole batch may bear the CE marking.
Applicable to: highly standardised, mass-produced medium-low-risk products (such as tools and some plastic products).
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Module H – Conformity based on full quality assurance
(High risk, whole-life-cycle control)
Procedure: the manufacturer establishes a quality system covering the entire process, and the notified body audits and supervises it throughout to ensure every stage complies with the regulations.
Applicable to: high-risk, complex system products (such as large medical equipment, lifts and industrial robots).
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Module H1 – Conformity based on full quality assurance plus design examination
(High risk, enhanced design review)
Procedure: in addition to the full quality system, the notified body also examines the product design (such as structural safety and material compliance) to ensure the design itself meets requirements.
Applicable to: products with highly complex designs where design defects could cause serious risks (such as aerospace components and high-pressure equipment).
(2) Modules commonly combined with Module B
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Module B + C – EU-type examination B + conformity to type C (medium risk, self-control after type approval)
Module B step: the notified body fully tests a “representative sample” and issues an “EU-type examination certificate” (proving the design conforms).
Module C step: the manufacturer declares that series products conform to the “certified type” and controls production consistency itself.
Applicable to: medium-risk products with a fairly fixed design (such as small appliances and ordinary machinery).
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Module B + C1 – EU-type examination B + conformity to type C1 (medium risk, periodic third-party testing after type approval)
Module B step: as for Module B above (type examination).
Module C1 step: the manufacturer ensures series products conform to the certified type and periodically commissions third-party testing (similar to the supervised testing in Module A1).
Applicable to: medium-risk products that need “periodic testing as evidence” (such as some electronic toys and household machinery).
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Module B + C2 – EU-type examination B + conformity to type C2 (medium risk, random checks after type approval)
Module B step: as for Module B above (type examination).
Module C2 step: the manufacturer ensures series products conform to the certified type and accepts random checks by the notified body (similar to the random checks in Module A2).
Applicable to: medium-risk products that need “random oversight” (such as some building hardware and power tools).
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Module B + D – EU-type examination B + production quality assurance D (medium risk, production process control after type approval)
Module B step: as for Module B above (type examination).
Module D step: the manufacturer establishes a production quality system (as in Module D1), and the notified body monitors its operation to ensure series production conforms to the certified type.
Applicable to: medium-risk products requiring a stable production process (such as industrial motors and standardised machine parts).
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Module B + E – EU-type examination B + product quality assurance E (medium risk, control of individual inspection after type approval)
Module B step: as for Module B above (type examination).
Module E step: the manufacturer inspects every product, and the notified body monitors the inspection process (as in E1).
Applicable to: medium-risk products where each item must conform (such as some medical equipment accessories and protective gloves).
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Module B + F – EU-type examination B + product verification F (medium-high risk, in-depth third-party verification after type approval)
Module B step: as for Module B above (type examination).
Module F step: the notified body fully verifies series products (as in Module F1) to con
firm conformity with the certified type.
Applicable to: medium-high-risk products requiring in-depth third-party involvement (such as new machinery and high-voltage electronic equipment).
In practice, the EU directive applicable to the product specifies which modules must be used (for example, the Machinery Directive (MD) requires Module B+F for high-risk machinery, and the MDR requires Module H1 for high-risk products). Companies do not choose modules themselves; they simply follow the directive’s requirements.
Overall there are three steps: identify the EU directive applicable to the product → consult the directive’s “conformity assessment” chapter to determine the product’s risk level → match the risk level to the module (or combination) specified by the directive. The examples below explain this in detail:
Step 1: Identify the EU directive applicable to the product
All CE marking requirements are based on EU directives. Different products are governed by different directives, and each directive directly specifies the conformity assessment modules (or permitted options) for that product type.
Examples of common products and directives:
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Electrical and electronic products (such as mobile phones, lamps and household appliances) → Low Voltage Directive (LVD 2014/35/EU) + Electromagnetic Compatibility Directive (EMC 2014/30/EU);
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Machinery (such as machine tools, crushers and lifts) → Machinery Directive (MD 2006/42/EC);
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Medical devices (such as scalpels and CT scanners) → Medical Device Regulation (MDR 2017/745);
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Personal protective equipment (such as safety helmets and protective clothing) → PPE Regulation (2016/425);
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Construction products (such as water pipes, doors and windows) → Construction Products Regulation (CPR 305/2011).
Step 2: Determine the module based on the directive’s “risk classification”
Most directives subdivide products by “risk level”, with different conformity assessment modules for each level. The higher the risk, the stricter the module (and the deeper the third-party involvement).
Examples:
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Machinery Directive (MD):
Low-risk “ordinary machinery” → Module A (self-declaration) or B+C (type examination + self-control);
High-risk “dangerous machinery” (such as presses and woodworking machinery) → B+F (type examination + third-party product verification) is mandatory, with notified body involvement.
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Medical Device Regulation (MDR):
Low-risk Class I devices (such as non-sterile medical gloves) → Module A (Is, Ir and Im require A1);
Medium-risk Class IIa/IIb (such as syringes and ultrasound scanners) → Module B+C2 or B+D;
High-risk Class III (such as coronary stents and artificial hearts) → Module H1 (full quality assurance + design examination).
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Personal Protective Equipment (PPE):
Low risk (such as ordinary gloves) → Module A;
Medium risk (such as safety helmets) → Module B+C;
High risk (such as diving suits and firefighting suits) → Module B+D or B+E.
Step 3: Check whether a combination of modules is required
Some products require a combination of two modules (such as B+C or B+F), which is clearly stated in the applicable directive.
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