RED conformity assessment: modules A, B+C and H

Hugues Orgitello updated 7 Oct 2026 13 min read

Article 17 of Directive 2014/53/EU offers three conformity assessment procedures: module A (Annex II), modules B and C (Annex III) and module H (Annex IV). Which ones are open depends on the essential requirement, not on the product: safety, EMC and the common charger can always be self-declared, while radio spectrum use and the activated Article 3(3) requirements need a notified body as soon as the cited harmonised standards are not applied in full. This page reads Articles 10 and 17 to 21 and Annexes II to IV as published, with the Commission RED Guide where it interprets them, as of 7 October 2026.

What Article 17 actually says

Article 17(1) sets the scope of every assessment, whatever the module: it covers "all intended operating conditions", also "the reasonably foreseeable conditions" for safety (Article 3(1)(a)), and, where the equipment can take different configurations, it must confirm compliance "in all possible configurations". The procedure is then chosen requirement by requirement.

Essential requirement	Harmonised standards cited in the OJ applied in full	Not applied, applied in part, or none exist	Article
3(1)(a) health and safety	A, B+C or H	A, B+C or H	17(2)
3(1)(b) EMC	A, B+C or H	A, B+C or H	17(2)
3(4) common charger	A, B+C or H	A, B+C or H	17(2), as amended by Directive (EU) 2022/2380
3(2) effective use of the radio spectrum	A, B+C or H	B+C or H	17(3) and 17(4)
3(3) activated by a delegated act, for example (d), (e), (f)	A, B+C or H	B+C or H	17(3) and 17(4)

The RED Guide draws the consequence: a notified body can only be mandatory for Article 3(2) and 3(3). A manufacturer who must use a notified body for 3(2) may still self-declare 3(1) and 3(4) under module A, and may use a different notified body for each "aspect" (3(1)(a), 3(1)(b), 3(2), each activated point of 3(3), 3(4)).

Article 1(4) and the RED Guide (section 10.5) settle the overlap with other directives: radio equipment in the scope of the RED is not subject to the LVD (2014/35/EU) except through Article 3(1)(a), nor to the EMC Directive. There is no separate LVD or EMC procedure, and a single EU declaration of conformity covers every Union act that requires one (Article 18(3)).

The three procedures, annex by annex

	Module A (Annex II)	Modules B + C (Annex III)	Module H (Annex IV)
Who assesses the design	The manufacturer, on its sole responsibility	A notified body examines the technical documentation and supporting evidence	The manufacturer, under a quality system approved by a notified body
Specimen examined by the body	None	None: Annex III point 2 provides "design type" examination, "without examination of a specimen"	None by default; the body may test during unexpected visits (point 4.4)
Body output	None	EU-type examination certificate, with "the conditions (if any) for its validity"	Quality system approval, audit reports
Production	Internal control (point 3)	Internal control, conformity to the certified type (module C)	Approved quality system for design, manufacture, final inspection and testing
Surveillance	None	None during production; the body follows the state of the art (point 7)	"Periodic audits" and possible unexpected visits (points 4.3 and 4.4)
NB number after the CE marking	No	No	Yes (Article 20(3))
Retention by the manufacturer	Technical documentation and DoC, 10 years	Same, plus the certificate, annexes and additions (point 9)	Same, plus quality system documentation, approved changes and body decisions (point 6)

Module A: internal production control

The manufacturer draws up the technical documentation under Article 21, ensures the manufacturing process keeps production compliant with it, affixes the CE marking and draws up the EU declaration of conformity (Annex II points 2 to 4). Module A does not require an accredited laboratory: the directive says nothing about who performs the tests.

For a 2.4 GHz Wi-Fi or BLE product, module A covers Article 3(2) when the cited editions of EN 300 328 and EN 301 489-17 are applied in full, and, if the product falls under Delegated Regulation 2022/30, when EN 18031 is applied without hitting one of its restrictions. Standards such as EN 62311 or EN 62368-1 are not in the RED list; they are "other technical specifications" for Article 3(1)(a), which module A covers anyway (see RED tests and technical file).

Modules B + C: EU-type examination, then conformity to type

Under Annex III, the manufacturer lodges an application with "a single notified body of his choice", with a written declaration that it has not been lodged elsewhere (point 3). The file contains the technical documentation, "an adequate analysis and assessment of the risk(s)", and the supporting evidence for the design, which must mention the documents used "in particular where the relevant harmonised standards have not been applied or have not been fully applied". Test results may come from the manufacturer laboratory or another laboratory "on his behalf and under his responsibility".

The body examines that documentation, writes an evaluation report and, if the type complies, issues the EU-type examination certificate (points 4 to 6). The RED Guide adds four points that matter in practice:

the manufacturer states in its mandate which essential requirements the body assesses (for example 3(1)(b) and 3(2), not 3(1)(a));
the certificate is issued per whole aspect; for a multi-radio product where one radio has no cited harmonised standard, the 3(2) certificate "should cover all radio parts";
where a radio part already holds an EU-type examination certificate, the body "may accept the results of that previous examination" without repeating it;
the body informs the Member States of certificates issued where cited harmonised standards were not applied or not fully applied (Annex III point 8), but not where no standard exists.

Typical cases: a proprietary modulation in an 868 MHz band that the cited EN 300 220 part does not cover; a product falling under Article 3(3)(d), (e) or (f) where an EN 18031 restriction applies (see below); a product whose manufacturer keeps a superseded standard after its withdrawal date (RED Guide, section 6.3).

Module C then makes the manufacturer responsible for production conformity to the approved type, with no further body involvement. The RED sets no validity period for the certificate: it carries "the conditions (if any) for its validity". The body must tell the manufacturer when changes in the state of the art mean the type may no longer comply, and the manufacturer must report every modification of the type that may affect conformity; such modifications need "an addition to the original EU-type examination certificate" (point 7).

Module H: full quality assurance

Under Annex IV, the manufacturer operates a quality system approved by a notified body for design, manufacture, final inspection and testing. The application includes the technical documentation "for each radio equipment type intended to be manufactured" (point 3.1(b)). The audit team must include "at least one member experienced as an assessor in the relevant radio equipment field", and the audit includes a visit to the premises (point 3.3). The body then carries out "periodic audits" and may make unexpected visits with tests (points 4.3 and 4.4). Annex IV fixes no audit frequency. Intended changes to the quality system must be notified to the body, which decides whether reassessment is needed (point 3.5).

The RED Guide states that where the quality system is already certified by an accredited certification body, the notified body "will normally not duplicate" those assessments but will check the directive-specific issues.

When a notified body is required in 2026

Situation	Requirement concerned	Basis
No cited harmonised standard for the band or technology, or one applied only in part	3(2)	Article 17(4)
Equipment under Delegated Regulation 2022/30 assessed without EN 18031, or with a deviation from it	3(3)(d), (e) or (f)	Article 17(4)
EN 18031-1, -2 or -3 applied with the option letting the user "not to set and use any password" (clauses 6.2.5.1 and 6.2.5.2)	3(3)(d), (e) or (f)	Decision (EU) 2025/138, notice 2
Toy or childcare radio equipment under EN 18031-2 clauses 6.1.3 to 6.1.6 without parental or guardian access control	3(3)(e)	Decision 2025/138, notice 3
Secure updates assessed against EN 18031-3 clause 6.3.2.4: no presumption in any case	3(3)(f)	Decision 2025/138, notice 3
Standard withdrawn from the OJ list, the manufacturer keeps applying it	3(2) or 3(3)	RED Guide, section 6.3
Manufacturer chooses module H for any requirement	All covered	Article 17(2) to (4)

The RED Guide adds that where a restriction is attached to a cited standard, the body is needed only if the restriction applies: "If the manufacturer is certain, that the restriction does not apply to the radio equipment, then the involvement of the Notified Body is not needed."

To find a body, search the NANDO database (Single Market Compliance Space) under Directive 2014/53/EU. Bodies can be notified for some essential requirements only (for example a specific Article 3(3) act), for Annex III, Annex IV or both, and for selected equipment types (RED Guide, section 7.2), so check the scope line by line. The notified body selection guide explains how.

Project sequence under the text

The order below follows the obligations of Articles 10, 17, 18, 20 and 21. Durations depend on the product and the laboratories, and the directive sets none.

Scope and requirements. Confirm the product is radio equipment and not excluded by Annex I or Article 1(3) (see scope). List the essential requirements that apply, including whether the product falls under Delegated Regulation 2022/30 for Article 3(3)(d), (e) and (f), and the other Union acts (RoHS, ecodesign, the CRA from 11 December 2027).
Configurations and risk analysis. Identify every operating mode and configuration (Article 17(1)); for multimode equipment the RED Guide limits this to modes that may legally be used in EU, EEA and EFTA countries. Write the risk analysis, which the RED Guide requires in the file whatever the procedure.
Standards and procedure, per requirement. Select the cited editions in Decision 2022/2191 as amended (see RED standards), check every restriction in the citation, and decide for 3(2) and 3(3) whether module A is still open.
Tests. Run the tests the chosen standards or other specifications require, in the laboratory of your choice for module A (see RED tests).
Notified body, if needed. Lodge the Annex III application with one body, or the Annex IV quality system application.
Technical documentation and DoC. Complete Annex V, draw up the DoC to the Annex VI model, and the simplified DoC (Annex VII) if used (see technical file).
Marking and accompanying information. CE marking (and NB number under module H), type or serial number, manufacturer name and postal address, instructions with frequency bands and maximum transmitted power, DoC copy or simplified DoC, and the Article 10(10) information where use is restricted.
After placing on the market. Keep the documentation 10 years (Article 10(4)), keep series production compliant and take account of design changes and changes in standards (Article 10(5)), act on non-conformities (Article 10(11)).

CE marking and the notified body number

Rule	Text
Affixed "visibly, legibly and indelibly" to the equipment or its data plate, unless not possible or not warranted by its nature	Article 20(1)
Also affixed "visibly and legibly" to the packaging	Article 20(1)
Affixed before placing on the market	Article 20(2)
May be lower than 5 mm, provided it remains visible and legible	Article 19(2)
Followed by the NB number only where the Annex IV procedure (module H) is applied, at the same height as the CE marking	Article 20(3)
NB number affixed by the body, or under its instructions by the manufacturer or authorised representative	Article 20(3)

The NB number has four digits (RED Guide). Under modules B + C the CE marking stands alone, even though a body issued the certificate. The RED Guide notes that the smaller-than-5 mm option cannot be used where another applicable act does not allow it, and gives RoHS as the example. A digital CE marking can only be added to the physical one. For the graphic rules see CE marking dimensions.

Dated changes that affect the procedure

Date	Act	Effect
13 June 2016	Directive 2014/53/EU	RED applies
30 January 2025	Implementing Decision (EU) 2025/138 (adopted 28 January 2025, published in the OJ and in force 30 January 2025)	EN 18031-1, -2 and -3 added to the RED list with restrictions
1 August 2025	Delegated Regulation (EU) 2022/30	Article 3(3)(d), (e) and (f) apply to the equipment it covers; module A for those points only with EN 18031 applied in full
16 February 2026	Delegated Regulation (EU) 2026/339 (OJ, 29 April 2026)	Adopted: repeals 2022/30 with effect from 11 December 2027
11 June 2027	Implementing Decision (EU) 2025/2499	EN 300 220-2 V3.1.1 loses its citation; keeping it after that date means a notified body for 3(2)
11 December 2027	Delegated Regulation 2026/339, Regulation (EU) 2024/2847	2022/30 repealed and the CRA applies in full; equipment placed on the market from 1 August 2025 to 10 December 2027 remains subject to market surveillance on 3(3)(d), (e) and (f) (recital 5)

Modifications after placing on the market

The directive gives three hooks, not a list of cases:

Series production. Article 10(5): changes in design or characteristics, and changes in the harmonised standards on which conformity is declared, "shall be adequately taken into account".
Type certificates. Annex III point 7: any modification of the approved type that may affect conformity or the conditions of validity needs an addition to the certificate.
Products already on the market. The RED Guide (section 1.5), applying chapter 2.1 of the Blue Guide, treats a software update as maintenance unless it modifies the original intended functions, radio interface, type or performance in a way not foreseen in the initial risk assessment, or changes the nature of the hazard or increases the level of risk. In that case the product is treated as a new product.

The technical documentation must be "continuously updated" (Article 21(2)), so each change and its assessment go into the file. For practical rules see component substitution and change management.

Two provisions on software-defined radio (SDR), Article 4 and Article 3(3)(i), are not active: the RED Guide states "currently no delegated act" for each.

Claims the texts contradict

Common claim	What the text says
"Module A requires every applicable harmonised standard, including 3(1)(a) and 3(1)(b), to be applied in full."	Article 17(2): for 3(1) and 3(4), A, B+C or H are always available. The condition applies to 3(2) and 3(3) only (Article 17(3) and (4)).
"Under module B the notified body examines a representative sample."	Annex III point 2 of the RED provides only design-type examination, "without examination of a specimen".
"Under module B+C the NB number follows the CE marking."	Article 20(3): only where Annex IV (module H) is applied.
"The CE marking must appear on the product, the packaging and the instructions."	Article 20(1): on the equipment or its data plate and on the packaging. The instructions are not mentioned.
"Module H means annual surveillance audits."	Annex IV point 4.3 says "periodic audits" and sets no frequency; point 4.4 adds possible unexpected visits.
"An EU-type examination certificate is valid five years."	The RED sets no period: the certificate states "the conditions (if any) for its validity" (Annex III point 6).
"A RED radio product also needs an LVD and an EMC assessment."	Article 1(4) excludes RED equipment from the LVD except through Article 3(1)(a); the RED Guide (section 10.5) says the LVD and EMC Directive do not apply. One DoC covers all applicable acts (Article 18(3)).
"Module A needs tests in an ISO/IEC 17025 accredited laboratory."	Annex II does not say who tests; under Annex III, tests may come from the manufacturer laboratory.
"Applying EN 18031 always gives module A for cybersecurity."	Decision 2025/138 removes presumption when the no-password option is used, when parental control is missing for toys and childcare equipment, and always for EN 18031-3 clause 6.3.2.4.
"One notified body must cover the whole product."	The RED Guide allows a different body for each aspect, and module A for 3(1) and 3(4) even when 3(2) goes to a body.
"SDR equipment needs a list of authorised hardware and software combinations in the file."	Article 4 and Article 3(3)(i) depend on delegated acts; the RED Guide states there are none.

Several of these claims appeared on an earlier version of this page, together with cost and lead-time ranges and a list of notified bodies that we could not source; they have been removed.