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Pressure testing of DB tank

Both Leak & Structural test 

Test head: 

The greater of – 

  • Top of the overflow
  • To 2.4m above top of tank 
  •  To bulkhead deck 

 Procedure:

  • Fill tanks by gravity to sea level.
  • A ballast pump can be used if the vessel wishes, but is not recommended.
  • If there are scuppers, then block scuppers as would be required for bunkering operations. 
  • Close sounding pipes tightly if these are at deck level. 
  • Open, or take off, air vent tops. 
  • Top up tank through air vents by fire hose until (assuming stern trim) water level is close to top of aft air vents. 
  • Ensure that fire hose can be stopped quickly as water level nears top of air vent. 
  • Check by sounding or ullage through the air vent, that water level in forward air vents has also risen towards top of air vents.
  • Hold level for 30 minutes minimum and check if level in vent is falling or steady. 
  • Look for leaks.

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