Does integrating a CE-marked radio module make my product compliant?

No. The Blue Guide 2022 states that "the fact that components or parts are CE marked does not automatically guarantee that the finished product also complies". The manufacturer of the finished product draws up its own technical documentation and EU declaration of conformity, and RED Article 17(1) requires the assessment to take into account all intended operating conditions and every configuration of the equipment.

Can a non-EU manufacturer sell CE products online directly to EU buyers?

Only if an economic operator established in the Union is responsible for the product. Since 16 July 2021, Article 4 of Regulation (EU) 2019/1020 requires one (EU manufacturer, importer, authorised representative with a written mandate, or fulfilment service provider) for products under the acts it lists, including the EMC Directive, the LVD, RED and RoHS, with its name and contact details on the product, packaging, parcel or an accompanying document.

Must the CE marking be at least 5 mm high?

Regulation (EC) No 765/2008, Annex II, sets 5 mm as the minimum where specific legislation does not impose other dimensions, and the proportions of the graduated drawing must be kept. RED Article 19(2) allows a lower height on radio equipment provided the marking remains visible and legible.

Do I need a new EU declaration of conformity when a harmonised standard is revised?

The Blue Guide 2022 says the declaration must be kept up to date: when any of its elements changes, including the versions of the harmonised standards, the declaration is updated for products placed on the market after that change. RED Article 10(5) also requires changes in the harmonised standards to be adequately taken into account in series production.

Does the RED cybersecurity requirement apply to every connected radio product?

No. Delegated Regulation (EU) 2022/30, applicable from 1 August 2025 after Delegated Regulation (EU) 2023/2444, activates Article 3(3)(d) for internet-connected radio equipment, 3(3)(e) for internet-connected, childcare, toy and wearable radio equipment that processes personal, traffic or location data, and 3(3)(f) for internet-connected equipment that transfers money. Equipment under the medical device regulations is excluded from all three.

CE marking pitfalls: 18 errors the texts settle

Hugues Orgitello updated 7 Oct 2026 16 min read

Each pitfall on this page is tied to the text that settles it: an article of the EMC Directive, the LVD, RED, Regulation 765/2008 or Regulation 2019/1020, a passage of the Commission Blue Guide 2022, or an Official Journal decision. No ranking or frequency is claimed; what matters is that each error is checkable against a text before the product is placed on the market. The eighteen pitfalls fall into three families: scoping, documentation and maintenance.

The pitfalls and the texts that settle them

#	Pitfall	Text that settles it	What the text says
1	Radio product assessed under EMC and LVD only	RED Article 2(1)(1); EMC Directive Article 2(2)(a)	Any product that intentionally emits or receives radio waves is radio equipment; the EMC Directive does not apply to it
2	Class A product sold for homes	EMC Directive Article 18(2)	Equipment not compliant in residential areas carries a clear indication of that restriction
3	Authorised representative without a written mandate	RED Articles 2(1)(13) and 11; Regulation 2019/1020 Article 5(2)	The representative exists only through a written mandate, which it shows to authorities on request
4	Distance sale with no EU economic operator	Regulation 2019/1020 Articles 4 and 6	Since 16 July 2021, products under the listed acts are placed on the market only if an EU economic operator is responsible for them
5	Finished product relying on CE-marked parts	Blue Guide 2022, section 2.1	CE-marked parts do not automatically make the finished product compliant
6	Module test results reused outside their configuration	RED Article 17(1)	The assessment covers all intended operating conditions and every configuration
7	DoC citing a superseded harmonised standard	Blue Guide 2022, section 4.1.2; RED Article 17(4)	After the transitional period only the revised standard gives presumption
8	DoC signed before the evidence exists	RED Articles 10(3) and 18(1)	The DoC is drawn up where compliance "has been demonstrated"
9	Component evidence missing from the file	LVD Annex III, module A point 2	The file includes drawings and schemes of components, calculations and test reports
10	Deformed or undersized CE marking	Regulation 765/2008 Article 30(5) and Annex II; RED Article 19(2)	Graduated-drawing proportions, 5 mm minimum unless the act allows less
11	Instructions in the wrong language	RED Article 10(8); LVD Article 6(7)	A language easily understood by end users, as determined by the Member State
12	DoC citing a repealed directive	EMC Directive Article 45; LVD Article 27; RED Article 50	2004/108/EC and 2006/95/EC repealed from 20 April 2016, 1999/5/EC from 13 June 2016
13	Product modified without updating the file	RED Article 10(5); Blue Guide 2022, section 2.1	Design changes are taken into account; a substantial modification can make a new product
14	No plan for withdrawal or recall	RED Article 10(11); Regulation 2019/1020 Article 4(3)	Immediate corrective action, and notification of authorities where there is a risk
15	Antenna changed in production	RED Articles 10(5) and 17(1)	The configuration assessed is the one being produced
16	Firmware changing radio behaviour	RED Articles 10(5) and 17(1); Blue Guide 2022, section 2.1	Changes to characteristics are taken into account before units are placed on the market
17	DoC not updated for later units	Blue Guide 2022, section 4.4; RED Article 18(2)	The DoC is continuously updated and covers each unit placed on the market
18	RED cybersecurity requirements missed	Delegated Regulation 2022/30, as amended by 2023/2444	Article 3(3)(d), (e) and (f) apply from 1 August 2025 to the categories listed

Family 1: Scoping errors

These errors arise before any test is run, so they can invalidate everything done afterwards.

1: Missing the RED directive on a "non-radio" product

RED Article 2(1)(1) defines radio equipment as an electrical or electronic product that "intentionally emits and/or receives radio waves for the purpose of radio communication and/or radiodetermination", including products that must be completed with an accessory such as an antenna to do so. A sensor with a Wi-Fi or BLE link used only for telemetry or updates falls under Directive 2014/53/EU. The function being secondary does not change that.

The consequence for the rest of the file is direct. The EMC Directive does not apply to equipment covered by RED (Article 2(2)(a) refers to Directive 1999/5/EC, which RED Article 50 says is read as a reference to RED), and electrical safety is assessed under RED Article 3(1)(a) "with no voltage limit applying". A DoC listing the EMC Directive and the LVD for a radio product cites the wrong acts.

How to avoid it: from the requirements stage, list every transmitter and receiver in the product, including third-party modules, and treat any of them as bringing the whole product under RED. See Scope.

2: Confusing Class A and Class B in EMC

Under EN 55032, Class B covers equipment intended primarily for residential environments and Class A the others; Class A equipment carries a warning that it may cause radio interference in a residential environment (see Tests). The directive itself sets the obligation behind that warning: EMC Directive Article 18(2) requires apparatus for which compliance with the essential requirements "is not ensured in residential areas" to be accompanied by a clear indication of that restriction of use, where appropriate also on the packaging.

A product that will be sold for homes and is tested only against Class A limits therefore has no presumption of conformity for the use it is sold for.

How to avoid it: decide the class from the intended use before design, not from the test results. A product that can be used in homes is assessed against Class B.

3: Authorised representative without a written mandate

RED Article 2(1)(13) defines the authorised representative as a person established in the Union "who has received a written mandate from a manufacturer". Article 11(2) sets the minimum the mandate must allow: keeping the DoC and technical documentation at the disposal of authorities for 10 years, providing information on reasoned request, and cooperating with authorities on action to eliminate risks. Article 11(1) excludes from the mandate the design obligations of Article 10(1) and drawing up the technical documentation. Regulation 2019/1020 Article 5(2) adds that the representative provides a copy of the mandate to market surveillance authorities on request.

An oral arrangement or a mention on a website is not a written mandate, so the person concerned is not an authorised representative within the meaning of the act.

How to avoid it: put the mandate in writing, list the tasks, and include at least those of RED Article 11(2) (or the equivalent article of the act concerned) and, where the representative is the Article 4 operator, the tasks of Regulation 2019/1020 Article 4(3). See Authorised representative and importer obligations.

4: Online sales without an EU economic operator

Article 4 of Regulation (EU) 2019/1020, applicable since 16 July 2021, provides that a product under the acts listed in Article 4(5) (among them the EMC Directive, the LVD, RED, RoHS and the Machinery Directive) "may be placed on the market only if there is an economic operator established in the Union" responsible for the tasks of Article 4(3). That operator is an EU manufacturer, an importer, an authorised representative with a written mandate, or a fulfilment service provider for the products it handles where none of the others exists. Its name and contact details go on the product or its packaging, the parcel or an accompanying document (Article 4(4)).

Under Article 6, an online offer is deemed to make the product available in the Union if it is targeted at end users in the Union. Online platforms, as information society service providers, must cooperate with authorities at their request (Article 7(2)).

How to avoid it: identify the Article 4 operator before the first EU sale and put its details on the product, packaging, parcel or accompanying document.

5: Underestimating sub-assembly scope

The Blue Guide 2022 (section 2.1) states that "the fact that components or parts are CE marked does not automatically guarantee that the finished product also complies". The manufacturer of a combination is responsible for selecting suitable parts, putting them together so that the whole complies, and for the EU declaration of conformity and CE marking of the finished product.

How to avoid it: assess each finished product in its final configuration, even if every part is individually CE marked.

6: Reusing a module's results without reassessing the final product

A pre-assessed Wi-Fi or BLE module was tested in a given configuration (antenna, ground plane, supply). RED Article 17(1) requires the conformity assessment to take into account "all intended operating conditions" and, where the equipment can take different configurations, to confirm compliance in all of them. The finished product is the equipment placed on the market, and its manufacturer signs the DoC for it.

How to avoid it: obtain the module integration conditions from its manufacturer, compare them point by point with the host product, record the comparison in the technical file, and repeat the radio and EMC tests that the differences affect.

Family 2: Documentation errors

These errors concern the technical file and the DoC.

7: Citing a superseded harmonised standard

The Blue Guide 2022 (section 4.1.2) explains that when a harmonised standard is revised, the Commission sets the date on which the superseded reference is withdrawn from the OJEU; during the transitional period both editions give presumption, and "after a transitional period, only the revised (superseding) harmonised standard gives a presumption of conformity". The Commission can shorten that period or end it immediately.

A product built to a superseded edition is not automatically non-compliant, but it has lost the presumption. Under the LVD, the technical documentation must then describe "the solutions adopted to meet the safety objectives" (Annex III, module A point 2(d)). Under RED, for Article 3(2) and 3(3), a manufacturer that has not applied a cited standard, or applied it only in part, must use a notified body procedure (Article 17(4)).

How to avoid it: check the current OJ list for each standard cited before signing each DoC. See Standards and Harmonised standards and presumption of conformity.

8: Signing the DoC before the evidence exists

RED Article 10(3) puts the order in the text: the manufacturer draws up the technical documentation and carries out the conformity assessment, and, where compliance with the applicable requirements "has been demonstrated by that conformity assessment procedure", draws up the DoC and affixes the CE marking. Article 18(1) adds that the DoC states that fulfilment of the essential requirements "has been demonstrated". A DoC signed before the test reports exist states something that is not yet true.

How to avoid it: release the DoC only once the reports it relies on are final and filed in the technical documentation.

9: Component evidence missing from the file

The LVD does not use the term "critical components". What Annex III (module A point 2) requires is a technical documentation that makes it possible to assess conformity and includes an analysis and assessment of the risks, "conceptual design and manufacturing drawings and schemes of components, sub-assemblies, circuits", the standards applied, results of design calculations and examinations, and test reports. RED Annex V lists the same drawings and schemes. Component approvals, where a standard relies on them, are part of that evidence.

How to avoid it: link the design bill of materials to the technical file, so that any component the risk assessment or the applied standard depends on has its evidence filed and is re-checked at each BOM revision. See Technical file.

10: Undersized or deformed CE marking

Regulation (EC) No 765/2008, Annex II, fixes the graphic form of the marking: if it is reduced or enlarged, the proportions given in the graduated drawing "shall be respected", and where specific legislation does not impose dimensions it is at least 5 mm high. RED Article 19(2) allows a lower height on radio equipment "provided that it remains visible and legible". Article 30(5) prohibits markings "likely to mislead third parties regarding the meaning or form of the CE marking".

How to avoid it: produce the marking from the graduated drawing, keep its proportions, and check height against the act concerned. See CE marking dimensions and visual rules.

11: Instructions in the wrong language, or machine-translated

The texts do not require "the official languages" of a Member State. RED Article 10(8) and LVD Article 6(7) require instructions and safety information "in a language which can be easily understood by consumers and other end-users, as determined by the Member State concerned". RED Article 18(2) requires the DoC to be translated into the language or languages required by the Member State where the equipment is placed or made available. The instructions and safety information must be "clear, understandable and intelligible" (RED Article 10(8)), which an unreviewed machine translation of safety warnings may not achieve.

How to avoid it: check the language rule of each target Member State and have the translated safety information reviewed by someone who knows the technical field. See User instructions and safety information languages.

12: DoC too generic or citing a repealed directive

A DoC identifies the Union acts it covers: where several acts require a DoC, RED Article 18(3) requires a single declaration containing "the identification of the Union acts concerned including their publication references". "All applicable directives" identifies none. Citing a repealed act is the other common defect: Directive 2004/108/EC (EMC) and Directive 2006/95/EC (LVD) were repealed with effect from 20 April 2016, and Directive 1999/5/EC (R&TTE) from 13 June 2016.

How to avoid it: keep one maintained DoC template listing each act by number and year, and check it whenever an act is replaced. See EU declaration of conformity.

Family 3: Maintenance errors

These errors arise after the first units are placed on the market.

13: Modifying the product without updating the file

RED Article 10(5) requires procedures "for series production to remain in conformity", and states that "changes in radio equipment design or characteristics" shall be adequately taken into account. The Blue Guide 2022 (section 2.1) goes further for important changes: a product whose original performance, purpose or type is modified, without this being foreseen in the initial risk assessment, and whose hazard or risk level has changed, may be a new product that needs a new conformity assessment. In every case the technical documentation is updated "in as much as the modification has an impact on the requirements", and tests on unaffected aspects need not be repeated.

How to avoid it: route every hardware change through a documented CE impact review before release. See Procedure and Component substitution rules.

14: No plan for withdrawal or recall

RED Article 10(11) requires a manufacturer that has reason to believe its equipment is not in conformity to "immediately take the corrective measures necessary to bring that radio equipment into conformity, to withdraw it or recall it, if appropriate", and, where it presents a risk, to immediately inform the national authorities of the Member States concerned. Article 10(5) asks manufacturers, where appropriate to the risks, to keep a register of complaints, non-conforming equipment and recalls. Regulation 2019/1020 Article 4(3) requires the EU economic operator to inform authorities of a risk and to cooperate on corrective action.

How to avoid it: decide before launch who triggers a withdrawal or recall, how distributors are reached, and how authorities are informed. See Product recall and EU Safety Gate response and Market surveillance and Safety Gate.

15: Antennas or accessories substituted after marking

The antenna is part of the configuration assessed under RED Article 17(1). A cheaper antenna with a different gain changes the radiated power, the emissions and the spectral mask behaviour on which Article 3(2) compliance was shown. RED Article 10(8) also requires the instructions to describe accessories, "including software", that allow the equipment to operate as intended.

How to avoid it: treat the antenna as a controlled part of the BOM; any substitution triggers a review of the Article 3(2) results and of the Article 3(1)(b) EMC results it affects.

16: Firmware changing radio behaviour without reassessment

A firmware change to output power, duty cycle, modulation or frequency bands changes the "radio equipment characteristics" of RED Article 10(5). Units placed on the market after the change must comply in their new configuration (Article 17(1)), and the Blue Guide criteria for a substantial modification apply if the change alters the performance or risk level.

How to avoid it: keep radio parameters under configuration control, so that a release changing them cannot ship without a CE impact review and updated evidence.

17: DoC not updated for later units

The Blue Guide 2022 (section 4.4) states that the DoC "must be kept up to date" and that when any of its elements changes, for example "changes in the versions of the harmonised standards", the version is updated for products placed on the market after that change. RED Article 18(2) says the DoC "shall be continuously updated". Each unit is placed on the market individually (Blue Guide, section 2.3), so units of an old model placed after new requirements apply "must comply with these new requirements".

How to avoid it: review active DoCs whenever a standard they cite is superseded in the OJ, and re-issue them, with new tests where the revised standard requires them.

18: Missing the RED cybersecurity requirements

Delegated Regulation (EU) 2022/30 activates RED Article 3(3)(d), (e) and (f). After Delegated Regulation (EU) 2023/2444 it applies from 1 August 2025, and not to "all connected radio products":

Requirement	Radio equipment concerned (Article 1)	Excluded (Article 2)
3(3)(d), network harm	Internet-connected radio equipment, directly or via other equipment	Equipment under Regulations (EU) 2017/745 and 2017/746
3(3)(e), personal data and privacy	Internet-connected equipment, childcare equipment, toys (Directive 2009/48/EC) and wearables, if they process personal, traffic or location data	The above, plus equipment under Regulations (EU) 2018/1139 and 2019/2144 and Directive (EU) 2019/520
3(3)(f), fraud	Internet-connected equipment that lets the user transfer money, monetary value or virtual currency	Same as 3(3)(e)

Every unit of an existing model placed on the market from 1 August 2025 must meet these requirements. EN 18031-1, -2 and -3 are cited with restrictions by Implementing Decision (EU) 2025/138; where a restriction applies, presumption is lost for that point and RED Article 17(4) requires a notified body procedure. See RED procedure.

The Cyber Resilience Act, Regulation (EU) 2024/2847, adds a second layer: its reporting obligations apply from 11 September 2026 and the rest from 11 December 2027 (Article 71). See Cyber Resilience Act.

How to avoid it: classify each radio product of the portfolio against the three rows above and record the result in its technical file.

Claims the texts contradict

Common claim (including earlier versions of this page)	What the text says
"The manual must be in the official languages of the Member State"	A language easily understood by end users, as determined by the Member State (RED Article 10(8), LVD Article 6(7))
"The CE marking must always be at least 5 mm high"	5 mm applies where the act imposes no other dimension; RED Article 19(2) allows less on radio equipment if visible and legible
"The LVD requires a list of critical components"	LVD Annex III lists drawings and schemes of components, calculations and test reports; the term is not in the directive
"Since 1 August 2025 RED cybersecurity applies to all connected radio products"	Only to the categories of Delegated Regulation 2022/30 Article 1, with the Article 2 exclusions
"Online platforms are now responsible for CE control"	Regulation 2019/1020 Article 7(2) requires them to cooperate with authorities at their request; the Article 4 operator carries the tasks
"Regulation 2019/1020 imposes a recall procedure on every manufacturer"	Recall duties come from the sectoral act (RED Article 10(11)) and the cooperation tasks of Regulation 2019/1020 Article 4(3)
"A DoC dated before the test reports is legally void"	No text says "void"; RED Article 10(3) ties the DoC to compliance having been demonstrated, so such a DoC states something untrue at signature
"A Class A product sold to consumers violates the essential requirements"	EMC Directive Article 18(2) requires a clear indication of the restriction of use; Class A limits are not set for residential environments (EN 55032)

In summary

Scoping errors (1 to 6): wrong act for a radio product, emission class not matched to use, no written mandate, no Article 4 operator for distance sales, reliance on CE-marked parts, module results reused outside their configuration.
Documentation errors (7 to 12): superseded standards, DoC signed before the evidence, component evidence missing, marking out of proportion, wrong language, repealed or unnamed acts in the DoC.
Maintenance errors (13 to 18): changes without a file update, no withdrawal or recall plan, antenna substitution, firmware changing radio behaviour, stale DoC, RED cybersecurity categories missed.

Each one can be checked against the article cited above during an independent review of the file before placing on the market.

Frequently asked questions

Does integrating a CE-marked radio module make my product compliant?: No. The Blue Guide 2022 states that "the fact that components or parts are CE marked does not automatically guarantee that the finished product also complies". The manufacturer of the finished product draws up its own technical documentation and EU declaration of conformity, and RED Article 17(1) requires the assessment to take into account all intended operating conditions and every configuration of the equipment.
Can a non-EU manufacturer sell CE products online directly to EU buyers?: Only if an economic operator established in the Union is responsible for the product. Since 16 July 2021, Article 4 of Regulation (EU) 2019/1020 requires one (EU manufacturer, importer, authorised representative with a written mandate, or fulfilment service provider) for products under the acts it lists, including the EMC Directive, the LVD, RED and RoHS, with its name and contact details on the product, packaging, parcel or an accompanying document.
Must the CE marking be at least 5 mm high?: Regulation (EC) No 765/2008, Annex II, sets 5 mm as the minimum where specific legislation does not impose other dimensions, and the proportions of the graduated drawing must be kept. RED Article 19(2) allows a lower height on radio equipment provided the marking remains visible and legible.
Do I need a new EU declaration of conformity when a harmonised standard is revised?: The Blue Guide 2022 says the declaration must be kept up to date: when any of its elements changes, including the versions of the harmonised standards, the declaration is updated for products placed on the market after that change. RED Article 10(5) also requires changes in the harmonised standards to be adequately taken into account in series production.
Does the RED cybersecurity requirement apply to every connected radio product?: No. Delegated Regulation (EU) 2022/30, applicable from 1 August 2025 after Delegated Regulation (EU) 2023/2444, activates Article 3(3)(d) for internet-connected radio equipment, 3(3)(e) for internet-connected, childcare, toy and wearable radio equipment that processes personal, traffic or location data, and 3(3)(f) for internet-connected equipment that transfers money. Equipment under the medical device regulations is excluded from all three.