Thief, static, and which other method are the three oil sampling methods commonly used aboard ships?

The correct method among the options provided is pressurized sampling. This method involves using a pressurized system to extract oil samples from machinery or fuel tanks, which helps ensure that the sample reflects the actual condition of the oil.

Pressurized sampling is essential because it minimizes the risk of contamination from air or external substances, ensuring a more accurate representation of the oil’s condition at the time of sampling. Using a pressurized technique also allows for samples to be taken from points that may be difficult to access, promoting effective monitoring and maintenance of oil quality aboard the vessel.

Other methods like gravity sampling involve relying on gravity to draw the oil into a container, which can introduce risks of contamination or inaccuracies if not performed correctly. Continuous flow sampling, while useful in some scenarios, is not as commonly cited as a standard procedure on all ships. Hence, pressurized oil sampling stands out as the preferred and most reliable method among those commonly utilized.