For a vehicle that will carry cold-chain equipment, the question to settle before price is which approval route the work falls under. Article 4 of Turkey's regulation on the manufacture, modification and assembly of vehicles defines two separate concepts: modification changes properties recorded in the vehicle's information package, while assembly consists of the Annex VI operations and does not require a revision of the system approval.
| Modification | Assembly | |
|---|---|---|
| Application | Per vehicle for one-off work, per type for series work (Article 5) | To the approval body under Annex VI (Article 5, item f) |
| Document issued | AİTM conformity certificate, for series work an AİTM type approval certificate (Article 6) | Annex V/D assembly conformity report (Article 6) |
This distinction is the first question for anyone setting up a cold chain with the vehicles you already have.
The assembly inspection follows control forms set by the approval body, and those forms are published on its website (Article 7), so you can see which items will be checked before ordering. Ask the upfitter in writing whether the job counts as modification or assembly and which document you will receive at the end; that decision is made by the authorised technical officer who signs the project and by the approval body.
