CE marking is a prerequisite for placing an electronic product on the European market. Yet many SMEs only discover the requirements of this certification during development — sometimes too late, sometimes vastly underestimating the timelines and cost involved. This practical guide covers the essentials so you are never caught off guard.
What is CE marking?
CE marking (Conformité Européenne) is a declaration by the manufacturer that their product meets the essential health, safety and environmental protection requirements defined by the applicable European directives. It is not a quality label, nor is it a certification issued by an external body in every case — it is a self-declaration backed by testing and a technical file.
For an electronic product, CE marking is not optional. It is illegal to place an electronic product on the European market without valid CE marking. Penalties range from market withdrawal to substantial fines, as well as civil and criminal liability for the manufacturer.
Directives applicable to electronics
A single electronic product may be subject to several directives simultaneously. The three main ones for electronic equipment are:
The RED Directive (Radio Equipment Directive — 2014/53/EU)
The RED Directive applies to any equipment that transmits or receives radio waves. It therefore covers all products incorporating Wi-Fi, Bluetooth, LoRa, 4G/5G, Zigbee, or any other wireless communication. It requires in particular the protection of the radio spectrum and the protection of networks.
Since August 2025, the RED Directive also includes strengthened cybersecurity requirements for Internet-connected equipment (Article 3.3 d/e/f), which directly impacts industrial IoT devices.
The LVD Directive (Low Voltage Directive — 2014/35/EU)
The LVD Directive applies to electrical equipment with an operating voltage between 50 V and 1,000 V AC, or between 75 V and 1,500 V DC. It covers risks related to the power supply: electric shock, overheating, electric arcing. For boards powered at low voltage (3.3 V, 5 V, 12 V), this directive generally does not apply directly.
The EMC Directive (ElectroMagnetic Compatibility — 2014/30/EU)
The EMC Directive applies to virtually all electronic equipment, whether or not it is mains-powered. It requires that the equipment does not emit electromagnetic disturbances beyond certain thresholds (emissions), and that it operates correctly in the presence of external disturbances (immunity). EMC tests are often the longest and most expensive part of the certification process.
Steps in the CE certification process
Step 1 — Compliance analysis and identification of applicable directives
Before any testing, you must determine which directives apply to the product. This analysis depends on the product's characteristics: supply voltage, presence of radio, intended use (consumer, industrial, medical environment…). A medical device or explosive atmosphere equipment (ATEX) will be subject to additional directives.
This step produces a list of applicable harmonised standards — the standards whose compliance is presumed to satisfy the essential requirements of the directives. For example, EN 55032 for EMC emissions of multimedia equipment, or EN 300 328 for radio emissions in the 2.4 GHz band.
Step 2 — Testing at an accredited laboratory
EMC and radio tests must be carried out on a prototype representative of the final version, in a COFRAC-accredited laboratory (or European equivalent). No internal pre-compliance testing replaces this step, even though such tests are strongly recommended beforehand to avoid costly surprises.
Typical tests for an industrial radio device include conducted and radiated emissions, electrostatic discharge (ESD) immunity, electrical fast transient (EFT) immunity, radio frequency and power emissions, and electrical safety tests if the LVD applies.
Step 3 — Compiling the technical file
The technical file brings together all documentation proving compliance: product description, electrical schematics, list of applied standards, test reports, risk analysis, and instructions for use. This file must be kept for at least 10 years after placing the product on the market and presented on request to market surveillance authorities.
Step 4 — EU Declaration of Conformity
Once testing has been completed and the technical file compiled, the manufacturer drafts and signs the EU Declaration of Conformity (DoC). This document identifies the product, lists the applied directives and standards, and attests under the manufacturer's responsibility that the product is compliant. The DoC must be supplied with the product or made available on the manufacturer's website.
Realistic timelines and costs to anticipate
CE certification timelines are often underestimated by product teams who have never been through the process. Here are typical figures for a standard electronic device (excluding medical and ATEX equipment):
- Compliance analysis: 1 to 2 weeks (in-house or with a consultant)
- Internal EMC pre-testing: 1 to 3 weeks (strongly recommended)
- Lead time to book an accredited laboratory slot: 4 to 10 weeks depending on the lab
- Lab testing (if passing first time): 3 to 5 working days
- Drafting the technical file and DoC: 2 to 4 weeks
In total, allow between 3 and 6 months for CE certification under the best conditions. If test failures require hardware modifications and re-testing, this timeline can double.
Common mistakes made by SMEs
- Integrating certification too late into the schedule — Starting to think about it 2 months before the launch date is systematically insufficient.
- Testing a non-representative prototype — The cabling, enclosure and power supply must be identical to the final version for the test to be valid.
- Using a certified radio module without repeating the tests — Integrating a certified module (e.g. a Bluetooth module) into a PCB does not exempt the final product manufacturer from their obligations under the RED Directive.
- Neglecting the technical file — An incomplete or poorly structured file exposes the company during a market inspection, even if the tests were passed successfully.
How Codium supports its clients
Codium is involved from the design phase to prepare the product for CE certification. Our approach includes:
- Analysis of applicable directives from the initial specification, so that compliance requirements are built into the design from the outset.
- EMC best practices at PCB level: plane separation, power supply filtering, shielding, routing topology adapted to emissions constraints.
- Connections with partner laboratories for pre-compliance testing and official testing.
- Assistance with compiling the technical file: schematics, BOM, functional description, user manuals.
Does your product need CE marking? Let's anticipate the constraints together from the design stage. Contact our design office.