(Refer to the detailed answer for 694a8e750457bfed0da63f81(b).) The NOx Technical File is the technical document (prepared under the NOx Technical Code) carried on board a ship that records the engine particulars and the settings/equipment by which the engine achieves the applicable NOx emission limit. It is important because it is the objective reference that proves the engine's compliance with MARPOL Annex VI Regulation 13, allows the flag/RO/port State to verify that the engine has not been modified outside the certified parameters, supports maintenance/modification control, and is a mandatory part of the IAPP certification and survey.

Contents: engine identification (manufacturer, model, serial/engine number, rated power/speed), the applicable NOx limit (Tier I/II/III) and the certified NOx value from the pre-certification test, a description of the emission control technology and the defining "engine configuration"/parameters (e.g. injection timing, rail pressure, valve timing, turbocharger adjustments and the emission control device), the retrofit/validation procedures, the maintenance/adjustment instructions, the engine adjustment record/log, and records of any modification that affects emissions.

Role: It supports the EIAPP certificate; the surveyor uses it to verify the engine is as certified, to identify any unauthorised or improper modification, and to check the effective operation of any SCR/EGR; it is checked at flag/RO surveys and by port State control; without an available and correct NOx Technical File the ship is non-compliant and may be detained for MARPOL Annex VI non-conformity.

Maintaining/updating:

• Keep the NOx Technical File on board and available.
• Follow the manufacturer's operation and maintenance procedures to keep the engine within the documented parameters; do not alter settings (timing, rail pressure, device settings) outside the approved data.
• Record any maintenance/calibration that could affect emissions in the log; carry out and document the periodic surveys/records.
• If a major engine modification that may affect NOx (e.g. changing injection, installing/removing an SCR, a major overhaul affecting the emissions) is made, the engine must be re-verified/re-certified against the NOx Technical Code and the File updated (a new/endorsed certificate) by the Administration/RO.
• The file is to be updated with the record of any such modification and any re-certification; the EIAPP endorsed accordingly at the ship's surveys. Any injection of the "emission control method" and its consumables (urea) are also monitored.

Consequences of non-compliance:

• The ship may not be allowed to operate in a NECA (or may be refused/expelled) and its IAPPC may be invalid.
• Port State control may detain the ship, issue deficiencies, and apply penalties (fines) under the local enforcement for MARPOL Annex VI.
• Failure of the NOx Technical File or altered engines may result in criminal/civil penalties, the vessel being refused entry to a port/ECA, and, for a fixed pattern, the flag may suspend the EIAPP requiring re-certification; a "MARPOL" non-compliance also damages the operator's record and may lead to detention and blacklisting.

Also note: Operating an engine whose NOx-relevant adjustment has been improperly changed is itself a breach of MARPOL and recurring non-compliance attracts serious sanction.