Traditionally, inspecting the underwater portions of a ship meant taking it out of the water and placing it in a dry dock – a costly and time-consuming process. In-water surveys (IWS) offer a modern alternative, allowing vital inspections to be carried out while the vessel remains afloat.

Why In-Water Surveys?

In-water surveys provide several advantages over traditional dry docking:

• Cost-effective: IWS eliminates the need for dry docking facilities, significantly reducing costs.
• Time-saving: Ships can be inspected quicker, minimizing downtime and keeping them operational.
• Environmental benefits: IWS reduces fuel consumption and emissions associated with dry docking procedures.

How In-Water Surveys Work

IWS utilizes divers and specialized equipment to examine the underwater hull, propeller, and other components. The process typically involves:

• Preparation: The inspection area is marked on the ship’s exterior to identify key components.
• Cleaning: Divers use specialized tools to clean the underwater surfaces, ensuring a clear view for inspection.
• Visual Inspection: Divers equipped with high-powered lights and cameras meticulously examine the underwater components.
• Thickness Gauging: Sonar or ultrasonic testing may be used to measure the thickness of the hull plating, identifying any areas of corrosion or wear.

Who Performs In-Water Surveys?

In-water surveys are conducted by qualified professionals with expertise in underwater inspections. These companies typically employ certified divers trained in using specialized equipment and adhering to strict safety protocols.

Regulations and Classification Societies

Classification societies, organizations that set safety standards for ships, play a crucial role in IWS. They establish guidelines for conducting in-water surveys and determine which vessels qualify for this method.

In-water surveys are not a replacement for dry docking altogether. However, they offer a valuable alternative for certain inspections, streamlining the process and reducing costs for ship operators.