Conformity Assessment Routes and Notified Body Involvement
The conformity assessment route determines how much of the technical documentation a notified body actually reads, so errors here propagate into every later part of an assessment.
Article 52: the route follows the class
Class I devices that are non-sterile, have no measuring function and are not reusable surgical instruments are self-certified: the manufacturer draws up technical documentation to Annexes II and III and issues an EU declaration of conformity under Annex IV. A Class I device that is sterile, has a measuring function or is a reusable surgical instrument keeps Class I status but needs a notified body for those aspects only, under Annex IX Chapter I and III limited to sterility or metrology.
Class IIa: Annex IX Chapters I and III, with technical documentation assessment on a representative sample per generic device group, or Annex XI Part A, which combines a full quality system assessment with product testing. Class IIb offers the same two options, but the Annex IX assessment covers each generic device group. Class IIb implantables must use Annex IX with assessment of the technical documentation of each device. Class III: Annex IX with per-device documentation assessment, or Annex X type-examination combined with Annex XI.
Certificates and scrutiny
Certificates under Annex XII are valid for a maximum of five years and are subject to surveillance, including unannounced audits. Class III implantable devices also trigger the Article 54 scrutiny procedure, in which the notified body's clinical evaluation assessment is reviewed by an expert panel.
IVDR
IVDR Article 48 mirrors the structure: a Class A device that is non-sterile and has no measuring function is self-certified; Class D requires a notified body plus an EU reference laboratory under Article 48(4).
Worked example
A manufacturer of a Class IIb orthopaedic implant proposes Annex X type-examination plus Annex XI Part A. This is refused: because the device is implantable, Annex IX is mandatory and the technical documentation of each device must be assessed rather than a sample.
Traps
Believing a type-examination certificate alone certifies a Class III device; assuming a sterile Class I device needs a full Annex IX certificate; forgetting that notified body designation is scoped by codes published in NANDO; and assuming a change of notified body resets the five-year certificate validity.