B08_Attachment_7_-_USCG_NAVIC_7-01_0001.pdf

This is a United States Coast Guard Navigation and Inspection Circular (NVIC 7-01) dated October 9, 2001, providing guidance on procedures for hull inspection and repair on vessels built with riveted construction.

The circular addresses the shortage of reliable information available to marine inspectors, surveyors, and vessel owners regarding best practices for inspecting and repairing older riveted hull steel vessels. The document establishes standards and procedures for rivet repair and replacement, referencing American Bureau of Shipping (ABS) Rules for Classification and Construction of Steel Vessels (1862-1969), Section 25, which specifies rivet diameter, spacing, plate thickness, and material testing standards. Key procedures include pre-inspection protocols requiring examination of the underwater body and assessment of any protective mastic coatings that may conceal defects; plate and joint preparation involving drilling, punching, reaming, and bolting techniques; riveting operations performed by five-person teams; and caulking to create watertight seals. The circular provides detailed guidance on inspection and testing of new rivets, inspection of existing rivets, and replacement and repair criteria. Acceptable repair methods for deteriorated rivets include bobbing (cold working the point), frenching (wedging the lip into the countersink with fine welding), and ring welding (temporary repairs only). The document specifies areas requiring special attention such as riveted butts in midbody deck and bottom plating, side shell plating seams, and locations subject to high stress or corrosive conditions. Documentation requirements mandate that Coast Guard marine inspectors record all examination details, mastic removal scope, and repairs completed in the Marine Safety Information System (MSIS). The circular emphasizes that improper repairs such as drilling plates and injecting epoxy between them are not acceptable.