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In Water Survey

Hull survey while ship is afloat done by authorized diving company with surveillance of Class surveyor as the replacement of docking survey

Requirements for IWS
  • Age not greater than 15 years. ( Ships of age 15 years and over may be permitted as special consideration)
  • All ships excluding Enhanced Survey Program (ESP) ships, such as Bulk carrier, Oil Tankers and Dangerous chemical bulk carrie rs of 15 years of age and over.
  • Ship with class “IWS” notation.
  • Need agreement of Flag administration.
  • High quality paint coating for 7.5 years extended dry docking (EDD).
  • Fitted effective anodes, fitted effective current corrosion protection (ECCP).
  • Access arrangements for - sea valves, rudder bearing & pintle clearance.
  • Stern tube wear down measurement, bow & stern thruster  -seal checking  
  • Survey plan,
  • Location and date of IWS,
  • Detail of hull marks and drawings.
Preparations in dry dock for IWS notation
  • Fitted approved Cathodic protection system.
  • Ship hull is in a satisfactory condition – shot blasted and painted with high quality paint
  • Fitted means for renewal and/or measuring of clearances of
  • Rudder bearings and bushes, stern tube wear down
  • Measures for checking of sea valves and sea chests.
  • Shell openings to be fitted gratings with hinged grid plates.
  • Hull paint color - to assist divers for inspection of hull in next IWS.
  • Mark clearly under-water hull fittings.
  • Mark transverse & longitudinal bulkheads
  • Mark tanks boundaries
  • Mark openings of shell plating for sea valves, docking plugs, thruster unit, stabilizer fins
  • Mark propeller blades with numbers
  • Mark for checking of any relative movements in next IWS
  • Liners on shaft    -bushes of rudder and stern frame
  • Drawings and folders containing above markings
  • Agreed blanking methods of any shell openings


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