Test benches and the Machinery Regulation from 2027-01-20

On 2027-01-20 Regulation (EU) 2023/1230 replaces Machinery Directive 2006/42/EC. For test bench engineering this is not a change of formalities: unlike the last transition, there is no period in which both sets of rules would be applicable side by side. What matters is solely when a plant is placed on the market or put into service.

With project durations of twelve to twenty-four months this means: quotations being costed today whose acceptance falls after the cut-off date already have to be designed and documented under the Regulation. This paper sorts out what changes — and which of it really affects test benches.

01 · The deadlines

Regulation (EU) 2023/1230 on machinery and repealing Directive 2006/42/EC is dated 2023-06-14 and was published in Official Journal L 165 of 2023-06-29.^{[1] [2]} It entered into force on 2023-07-19.^[3] Article 54(2) lays down: “It shall apply from 2027-01-20.” Individual articles apply earlier — the notification of notified bodies as early as 2024-01-20, the provisions on penalties from 2026-10-20.^[4]

Article 51(2) repeals Directive 2006/42/EC with effect from 2027-01-20. Article 52(1) protects what already exists: Member States may not impede the making available of products that were placed on the market under the Directive before that date. EC type-examination certificates under Article 12 of the Directive remain valid until they expire.^[4] The European Commission puts it briefly: all machinery placed on the EU market before 2027-01-20 must comply with the Machinery Directive in force.^[5]

02 · Regulation instead of Directive

The change of legal form is the structurally biggest difference. A directive has to be transposed nationally — in Austria by the Maschinen-Sicherheitsverordnung 2010.^[7] A regulation applies directly in all Member States, without an act of transposition.

In practice three things follow from this. First, for the export of individual plants there is no longer any need to check whether a destination state has transposed the Directive differently. Second, the citation changes: the EU declaration of conformity will in future cite Regulation (EU) 2023/1230, no longer the Directive or the national transposing regulation. Third, national legislation is nevertheless still needed — for market surveillance, the competence of authorities, notification and penalties.

Austria has already brought this framework up to date: the amendment BGBl. II No. 161/2025 of 2025-07-15 amends the Maschinen-Sicherheitsverordnung 2010, appoints the Bundesamt für Eich- und Vermessungswesen as market surveillance authority and requires the notification procedure for conformity assessment bodies to be carried out under Chapter V of Regulation (EU) 2023/1230 already.^[8] That corresponds exactly to the requirement in Article 54(3), under which those articles have applied since 2024-01-20.^[4]

03 · Substantial modification

For test benches this is the practically most important point of the whole Regulation, because test benches are extended continuously over fifteen to twenty years. Article 3(16) defines for the first time in EU law:

Recital 26 adds the decisive third stage: the modification should be regarded as substantial “where new significant protective measures are required”.^[1] With that, the three-stage test familiar from German interpretative practice — new hazard or increased risk, tolerable risk no longer under control, new protective measures required — is anchored in the text of the Regulation itself.

New, and directly relevant for test benches: purely digital modifications too can be substantial. A changed safety application in the safety PLC, a new parameter setting for a protective function, an additional remote access interface — all of that falls within the wording.

Who becomes a manufacturer as a result?

Article 18 governs the consequence, and the second half of the sentence is the most important change for plant engineering:

The manufacturer's obligations can thus be limited to the sub-machine actually affected — provided that the risk assessment demonstrates that the effect is limited. Anyone who replaces only the media conditioning module on an existing heat pump test bench does not necessarily have to reassess the entire plant. Without that documented demonstration, however, the full obligation applies to the whole assembly.

The practical consequence

The definition yields a sequence of checks for every conversion:

1. Is the modification foreseen or planned by the manufacturer? If it is — documented variants, defined expansion stages, released parameter ranges in the instructions for use — there is no substantial modification.
2. Does a new hazard arise, or does an existing risk increase?
3. Are new significant protective measures required?^[1]

To clarify who is a manufacturer at all: Article 3(18) expressly also covers anyone who puts products into service “for their own use”.^[9] A company that builds a test bench for its own laboratory is a manufacturer in the legal sense — with a risk assessment, technical documentation, conformity assessment, declaration of conformity, CE marking and instructions for use.

04 · Annex I: when a notified body becomes necessary

Annex I takes the place of the former Annex IV of the Directive and is newly divided into two parts.^[10]

A typical test bench for heat pumps, electronics cooling or power electronics is, as a whole, not contained in any category of Annex I. It therefore remains self-certifiable. What has to be checked, though, is whether components are affected — in particular logic units for safety functions and protective devices for the detection of persons, both listed in Part B.^[10] For bought-in safety PLCs and light curtains this obligation lies with the component manufacturer, not with the test bench builder.

The AI case

Annex I Part A lists two categories that did not exist in the Directive: safety components and machinery with embedded systems “with fully or partially self-evolving behaviour using machine learning approaches ensuring safety functions”.^[10] Systematically, the new definition in Article 3(3) fits with this, under which a safety component may also be a digital component “including software”.^[9]

Module G for one-offs

The Regulation provides no exemption for one-offs. For special-purpose machinery, however, it offers a fitting instrument: unit verification under Annex X, expressly named as an option in Article 25.^[10] For Part A products made as one-offs it is often more economical than a type-examination. Article 25(5) also requires notified bodies to take the interests of small and medium-sized enterprises into account when setting their fees.^[10]

05 · The test bench as an assembly of machinery

Contrary to what is often assumed, there is no separate definition of the “assembly of machinery”. The term appears in the definition of machinery itself, Article 3(1)(d): an assembly of machinery or of partly completed machinery “which, in order to achieve the same end, are arranged and controlled so that they function as an integral whole”.^[9]

Recital 33 gives the reason: the safety of the machinery as a whole depends on the dependencies and interactions between its components, “which can also result in an assembly of machinery”.^[1]

Anyone who puts such an assembly together and places it on the market or puts it into service for their own use is the manufacturer of the assembly — with their own risk assessment, in particular of the interfaces between the sub-machines, their own technical documentation, one declaration of conformity, one CE marking and instructions for use for the assembly.

On the supplier side the counterpart is partly completed machinery under Article 3(10) — an assembly “which does not yet constitute machinery” and which as such cannot perform a specific application.^[9] It does not bear a CE marking under the Regulation, but an EU declaration of incorporation under Article 22 and assembly instructions under Annex XI.^[10] Article 22(4) makes it clear: with the declaration of incorporation the manufacturer takes responsibility for the partly completed machinery meeting the requirements.

For drafting contracts this means: the roles belong settled in advance. Who manufactures the assembly, who supplies partly completed machinery with a declaration of incorporation and assembly instructions, who carries out the overall risk assessment of the interfaces. That is not a legal nicety; it determines who signs the declaration of conformity in the end.

06 · Digital instructions for use

Article 10(7) permits provision in digital form and attaches conditions to it. Those essential for plant engineering at a glance:^[9]

07 · Protection against corruption as a safety requirement

Under point 1.1.9, Annex III contains a requirement that did not exist in the Directive: the machinery must be designed and constructed in such a way that the connection of another device — through its own function or through a remote access device — does not lead to a hazardous situation.^[11]

Test benches are practically always networked: measurement data acquisition, test automation, connection to test bench management systems, often a remote maintenance access for the manufacturer. Point 1.1.9 thus makes protection against corruption and against remote access an essential safety requirement whose fulfilment has to be demonstrated in the risk assessment — not a question for the IT department.

The corrigendum of April 2025 reworded this very point several times^[6] — here the corrected version is the one to use.

08 · Other legal acts and the state of the standards

Electrical safety

Annex III point 1.5.1 contains the conflict rule verbatim: the safety objectives of Low Voltage Directive 2014/35/EU apply to machinery, “however, the obligations concerning conformity assessment and the placing on the market … with respect to hazards caused by electricity shall be governed solely by this Regulation”.^[11] In practice: apply EN 60204-1, but no additional declaration of conformity under the Low Voltage Directive for the machinery.

Explosion protection, EMC and pressure equipment

Annex III point 1.5.7 requires that, as regards the risk of explosion when used in a potentially explosive atmosphere, the machinery must comply “with the specific Union harmonisation legislation applicable thereto”.^[11] The ATEX Directive is therefore not named explicitly, but is brought in through this reference — for test benches with flammable refrigerants or hydrogen it is the decisive point of connection.

Article 21(3) does at least simplify the paperwork: where machinery is subject to several legal acts, each of which prescribes a declaration of conformity, only one single declaration has to be drawn up for all of them.^[10]

The state of the standards — the open flank

On 2025-01-20 the Commission issued the standardisation request to CEN and CENELEC.^[12] The work programme was to be submitted by 2025-07-20, and the final report is scheduled for 2035-01-20. According to the sources that can be found, a list of harmonised standards under the Regulation has so far not been published in the Official Journal.^{[13] [14]}

That considerably increases the weight of a cleanly documented risk assessment. For products under Annex I Part B it is additionally relevant to the module, because internal production control presupposes the full application of harmonised standards.^[10]

The relevant standards themselves are also in motion. State of the Austrian editions: EN ISO 12100 in the 2013 edition^[15], EN ISO 13849-1 in the 2023 edition^[16], EN 60204-1 in the 2019 edition^[17] and EN ISO 13850 in the 2016 edition.^[18] Both EN ISO 12100 and EN 60204-1 are under revision.^{[19] [20]} For a paper such as this one that means: always name standards with their edition date.

09 · Our preparation list

What we want to have worked through by January 2027. This is our list, not legal advice.

1. Extend the quotation templates to include the question of whether the customer wants the instructions for use on paper — documented at the time of purchase.^[9]
2. Infrastructure for ten years of online availability to be set up: a stable address, marking on the plant, a version archive.^[9]
3. Protection against corruption to be included as a separate item in the methodology of the risk assessment — remote maintenance, network segmentation, protection against reparameterisation.^[11]
4. Retention of the technical documentation to be checked for at least ten years.^[9]
5. Check on every project, whether Annex I Part A points 5 and 6 are affected — the only case in which an otherwise self-certifiable test bench must go to a notified body.^[10]
6. Anticipate expansion stages and provide for them in the instructions for use and the technical documentation, in order to keep later conversions out of substantial modification.^{[1] [9]}
7. Fix the roles in assemblies by contract — who is the integrator, who supplies partly completed machinery, who assesses the interfaces.^{[9] [10]}
8. With flammable refrigerants or hydrogen carry explosion protection along in parallel.^[11]

And one observation to close: nowhere does the Regulation demand anything that a careful builder of special-purpose machinery would not do anyway. It writes down a good deal of what was previously interpretative practice — in particular for substantial modification. The effort lies not in new protective measures but in the documentation and in the infrastructure behind it.

10 · Sources

All references were retrieved in August 2026. Where a secondary full-text reproduction was used because the official source did not extend as far as the article in question, this is noted in the source line.