According to the IACS UR M 20.5 being enacted, the following regulation has been added in NK Rules Part B Chapter 1 General and comes into effect from 1 January 2001.

" At the time of drydocking, a dock trial may be required at the discretion of the attending surveyor to confirm satisfactory operation of main and auxiliary machinery. If significant repairs are carried out to main or auxiliary machinery or steering gear, consideration is to be given to a sea trial to the attending Surveyor's satisfaction."

Therefore, at the time of drydocking, a dock trial may be required in the following cases at the discretion of the attending surveyor to confirm condition of the machinery.
1) When Main engine and/or Auxiliary machinery and/or Propulsion shafting system and/or Steering
gear were repaired or overhauled for inspection.
2) When docking work was conducted for two weeks or longer, even if there was no repairing work or
overhaul inspection of machinery.
It may be allowed to conduct mooring run for dock trial at the discretion of the attending surveyor.
In case that Auxiliary machinery and/or Steering gear were repaired or overhauled for inspection,
the operational test of the machinery concerned may be acceptable at the discretion of the attending surveyor.

When significant repairs for Main engine and/or Auxiliary machinery and/or Propulsion shafting system and/or Steering gear were conducted, the attending surveyor may require a sea trial at the discretion of the attending surveyor. However, upon significant repairs for Auxiliary machinery and/or Steering gear were conducted, the operational test of the machinery concerned may be acceptable at the discretion of the attending surveyor.

If you have any inquiries, please contact the Survey Department.
Tel: +81-3-5226-2027 or Fax: +81-3-5226-2029