Used and modified machinery conformity assessment FAQ

Start with the market boundary. Regulation (EU) 2023/1230 defines placing on the market as the first making available of an in-scope product on the Union market, and putting into service as the first use in the Union for its intended purpose. A second-hand machine that was already lawfully placed on the EU market is not automatically treated as newly placed on the market just because it is sold again.

The answer changes when the machine is first brought into EU use after being used outside the EU, or when a later modification crosses the substantial-modification test. In those cases, the team should treat the event as a conformity trigger instead of relying on the old declaration, old technical file, or a resale record alone.

Apply the substantial-modification test in sequence. The modification must occur after placing on the market or putting into service; be physical or digital; be outside what the manufacturer foresaw or planned; affect safety by creating a new hazard or increasing an existing risk; and require either guards or protective devices that change the existing safety control system, or additional protective measures for stability or mechanical strength.

Repairs and maintenance that do not affect compliance with the essential health and safety requirements should not be treated as substantial modifications. Planned manufacturer updates are also different from an unplanned third-party modification because the definition requires the change not to be foreseen or planned by the manufacturer.

If the event is first EU placing on the market, first EU putting into service, or a substantial modification by a professional operator, the responsible person cannot simply annotate the old file. For machinery and related products, Article 10 requires design and construction in line with Annex III, technical documentation under Annex IV Part A, the relevant Article 25 conformity assessment procedure, an EU declaration of conformity, CE marking, instructions, and retention of the technical documentation and declaration for market surveillance authorities.

For partly completed machinery, the evidence route is different: Article 11 points to Annex IV Part B technical documentation, an EU declaration of incorporation, and assembly instructions. Do not replace that with a machinery declaration unless the product has become complete machinery or a related product.

The record should let a market surveillance authority or decision owner see why the machine was treated as resale, first EU use, ordinary repair, planned update, or substantial modification. The evidence should not be a generic compliance statement; it should tie the actual modification to the legal test and the updated risk assessment.

Regulation (EU) 2023/1230 requires manufacturers to keep technical documentation and declarations available to market surveillance authorities for at least 10 years after machinery is placed on the market or put into service. Regulation (EU) 2019/1020 gives market surveillance authorities powers to require corrective action and, where risks persist, restrict, withdraw, or recall products.

Most errors come from skipping the boundary question. A team treats a used machine as automatically exempt, or treats every repair as a new machine, without documenting first EU use, the manufacturer's planned configuration, and whether the modification actually creates a new hazard or increases an existing risk.

The other frequent problem is evidence drift: the old declaration, old test report, or supplier file may still matter, but it does not prove the modified configuration unless the changed hazards, safety functions, instructions, and conformity route have been reassessed.