Harmonised Standards for Machinery: A, B and C Standards
Harmonised standards are the central tool machinery manufacturers use to demonstrate conformity with EU directives and regulations. This guide explains the three-tier standards system (A, B and C standards), the most important standards in machinery engineering and how the presumption of conformity works.
What are harmonised standards?
Harmonised standards are European standards (EN) drawn up by the European standardisation organisations (CEN, CENELEC, ETSI) at the request of the European Commission. They translate the essential health and safety requirements of an EU directive or regulation into technical specifications.
The decisive advantage: whoever applies a harmonised standard can rely on the so-called presumption of conformity. Applying harmonised standards is voluntary; there is no obligation to use a particular standard. However, a manufacturer who does not apply a harmonised standard must demonstrate by other means that the chosen solution achieves the same level of safety.
The presumption of conformity
The presumption of conformity is a central concept of the European single market. It says: if a manufacturer applies a harmonised standard whose reference is published in the Official Journal of the European Union, the product is presumed to meet the essential requirements covered by that standard.
In concrete terms this means that, in a dispute, the authority must prove that the standard was not complied with or that the standard does not fully cover the requirement. Without applying harmonised standards, the burden of proof lies entirely with the manufacturer.
Important: the presumption of conformity applies only if the reference of the standard is published in the Official Journal of the EU. Standards whose reference has been withdrawn or not yet published do not trigger a presumption of conformity. Check the status of the standards you apply regularly.
The A, B and C standards system
Harmonised standards for machinery are organised in a three-tier hierarchy:
A standards (basic safety standards)
A standards define basic concepts, principles for design and general aspects that apply to all types of machinery. They form the methodological foundation of machinery safety.
The most important A standard:
EN ISO 12100 (Safety of machinery: general principles for design, risk assessment and risk reduction). This standard is the basis of every risk assessment in machinery engineering.
B standards (generic safety standards)
B standards deal with individual safety aspects or safeguards relevant to many types of machinery. They are divided into B1 standards (particular safety aspects such as safety distances or noise) and B2 standards (safeguards such as interlocking devices or light curtains).
Important B standards:
- EN ISO 13849-1/-2 (safety-related parts of control systems: performance level, categories)
- EN 62061 (IEC 62061) (functional safety of safety-related control systems, SIL)
- EN ISO 13857 (safety distances to prevent hazard zones being reached)
- EN ISO 14119 (interlocking devices associated with guards)
- EN ISO 13850 (emergency stop function, principles for design)
- EN 60204-1 (electrical equipment of machines)
Proof of functional safety has two parts. You derive the required performance level (PLr) from the risk assessment; in the functional safety module you record it per safety function using the risk graph of EN ISO 13849-1. The calculation of the performance level actually ACHIEVED from category, MTTFd, DCavg and CCF, together with the manufacturers' component data (libraries per VDMA 66413), belongs in SISTEMA, the free tool of the IFA of the DGUV. CE-Copilot does not replace SISTEMA: you then enter the SISTEMA result in the module, the software checks PL against PLr for plausibility, and the SISTEMA report belongs in the technical file as evidence, in the section on plans and calculations.
C standards (machine safety standards / product standards)
C standards contain detailed safety requirements for a particular machine or group of machines. They take precedence over A and B standards: if a C standard sets different requirements from a B standard, the C standard applies to the machine type in question.
Examples of C standards:
- EN 12622 (safety of hydraulic press brakes)
- EN 619 (continuous handling equipment and systems: safety and EMC requirements)
- EN ISO 10218-1/-2 (industrial robots: safety requirements)
- EN 415 series (packaging machines)
How do I find the relevant standards for my machine?
Look for a C standard: First check whether a product-specific C standard exists for your machine type. The C standard usually contains references to all relevant A and B standards.
Always apply the A standard: EN ISO 12100 is always relevant. It forms the methodological basis of your risk assessment.
B standards depending on the hazard: Select B standards based on the hazards you have identified. Does your machine have a safety control system? Then you need EN ISO 13849 or EN 62061. Are there guards? Then check EN ISO 14119.
Check the OJEU citation: Make sure the reference of your standard is published in the Official Journal of the EU and that the standard has not been withdrawn. Only then does the presumption of conformity apply.
Standards and the EU Machinery Regulation 2027
With the new EU Machinery Regulation (EU) 2023/1230, harmonised standards have to be adapted and published under the new legal framework. During the transition period, existing standards can continue to be used provided they cover the requirements of the Regulation. The European Commission issued standardisation request M/605 to CEN and CENELEC for this purpose in January 2025.
For manufacturers this means: actively track which standards are being harmonised under the new Regulation and whether the standards you currently apply keep their validity. Tracking standards is particularly important during the transition period (up to January 2027 and beyond).
Find relevant standards automatically
The CE-Copilot standards finder automatically identifies the relevant harmonised standards for your machine type. It shows the current harmonisation status, checks the citation in the Official Journal of the EU and informs you about updates.
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