EU manufacturers placing machinery on the single market must perform and document a risk assessment under Machinery Directive 2006/42/EC Annex I, General Principle 1, with EN ISO 12100 supplying the recognised methodology for design, risk estimation and the three-step risk reduction cycle.
What the risk assessment obligation actually covers
Annex I, paragraph 1 of 2006/42/EC requires that "the manufacturer of machinery or his authorised representative must ensure that a risk assessment is carried out in order to determine the health and safety requirements which apply to the machinery" [S9] Pilz, MD guidance, 2025-08. The output is not paperwork for its own sake: it determines which Essential Health and Safety Requirements (EHSR) of Annex I apply, which harmonised C-type standards can be cited, and whether a Notified Body must be involved under Annex IV. EN ISO 12100 is the type-B harmonised standard that defines the procedure — machine limits, hazard identification, risk estimation, evaluation, and a documented iterative loop until residual risk is reduced as far as practicable [S8] CEN-CENELEC, EN ISO 12100 overview.
Self-certification versus third-party: when a Notified Body is forced
Two conformity assessment routes exist under 2006/42/EC: internal production control (Module A, self-certification with the manufacturer compiling the technical file and affixing the CE mark) and routes requiring a Notified Body for the categories listed in Annex IV [S3] cemarking.net, 2006/42/EC guide. Annex IV lists 23 categories of higher-risk machinery — circular saws, planers, presses, injection moulding machines for plastics, vehicle lifts, and machinery for pesticide application under Directive 2009/127/EC [S4] F2 Labs; [S5] HQTS, MD 2006/42/EC guide. A pressure transmitter feeding a safety function on a hydraulic press is not Annex IV by itself, but the press assembly typically is, so the safety instrumented function and the supporting servo-motor wiring inherit the notified-body pathway indirectly through the host machinery.
EN ISO 12100: the three-step risk reduction hierarchy
EN ISO 12100 codifies a hierarchy: (1) inherent safe design — eliminate the hazard or reduce risk by changing the machine itself; (2) safeguarding — guards, interlocks, two-hand controls, light curtains; (3) information for use — warnings, signals, operator training [S8] CEN-CENELEC. Risk reduction is iterative, not a one-shot checklist. The PLC controlling a guarded cell can act as a Category 3 / PL d safety stop under ISO 13849-1, but only if its I/O assignment, wiring and diagnostic coverage are documented in the risk assessment file alongside the mechanical guard, not as a replacement for it.
Custom risk assessment versus check-list: picking the method
For novel or one-off machinery, the iterative method in EN ISO 12100 is the default. For variants of an existing family, many OEMs maintain a check-list or modular hazard catalogue and re-run the delta assessment [S1] Guide to application of the MD, Edition 2.1, 2017. The delta approach is acceptable provided the check-list itself was derived from a full EN ISO 12100 assessment and each variant is signed off against the unchanged base hazard set — auditors trace the lineage back to the original assessment, not just the latest revision.
Real use cases: hydraulic presses, robotic cells, pesticide sprayers
Three concrete scenarios illustrate scope: a hydraulic press used in metal forming sits in Annex IV and requires Notified Body involvement for the safety-critical subsystems, including any industrial valve block on the clamp circuit if the valve is a listed safety component; a collaborative robot cell falls outside Annex IV if the integrator can show that ISO/TS 15066 power-and-force-limiting thresholds are met, but a flow-meter tied into a coolant loop is typically not a safety component; self-propelled pesticide application machinery falls under Directive 2009/127/EC layered on top of 2006/42/EC [S4] F2 Labs, with both the application machinery and the spray control electronics in scope of the risk assessment.
Limitations and common failure modes
The three most common audit findings on 2006/42/EC technical files: (a) hazard list copied from a previous machine without re-evaluation against the new machine's limits and intended use; (b) C-type standards cited as a substitute for the EN ISO 12100 risk assessment rather than as inputs to it; (c) information-for-use warnings promoted to a primary risk reduction measure, which reverses the hierarchy. The MD guide also flags machines supplied without a drive system: the risk assessment must include the loads, speed and inertia of every motor the end-user is likely to fit [S10] CEN-CENELEC MD Guide, Edition 2.1, 2017. EN ISO 12100 is not a checklist either — it explicitly demands iteration, not sign-off-and-file [S7] Kothes, MD risk assessment FAQ, 2021.
Transition timeline: what 2026-06-05 means in practice
Regulation (EU) 2023/1230 repeals Directive 2006/42/EC with effect from 20 January 2027 [S1] CEN-CENELEC, 2017. Until that date, 2006/42/EC remains the legal basis for CE marking; from 20 January 2027 the new Machinery Regulation applies directly, with no national transposition gap. CE teams that have not yet started harmonising their hazard catalogue, EN ISO 12100 references and Annex IV classification to the new text are working against roughly seven months of runway, and suppliers of pressure-sensor safety components should expect renewed requests for declarations of conformity aligned to the new regulation's Annex III well before Q4 2026.
Two trackable signals to watch in the second half of 2026: the European Commission working group on the new Machinery Regulation is expected to publish additional FAQ entries on Annex IV categories, and the Notified Body Operations Group typically refreshes its recommended list of C-type harmonised standards each autumn, which feeds directly into the EN ISO 12100 type-B bridge used in most machinery risk assessments.