---
kind: "section"
citation: "46 C.F.R. § 31.10-20"
title: "46"
number: "31.10-20"
heading: "Definitions relating to hull examinations—T/B ALL."
url: "https://uscodex.org/cfr/46/31.10-20"
---

# §31.10-20. Definitions relating to hull examinations—T/B ALL.


As used in this part—

- (a) Drydock examination means hauling out of a vessel or placing a vessel in a drydock or slipway for an examination of all accessible parts of the vessel's underwater body and all through-hull fittings.
- (b) Internal structural examination means an examination of the vessel while afloat or in drydock and consists of a complete examination of the vessel's main strength members, including the major internal framing, the hull plating, voids, and ballast tanks, but not including cargo or fuel oil tanks.
- (c) Cargo tank internal examination means an examination of the vessel while afloat or in drydock and consists of an examination of the internals of all cargo tanks; except, if the vessel is certificated to carry cargoes regulated under [part 38](/cfr/46/part38.md) or subchapter O of this chapter, the cargo tank internal examination must be accomplished as specified in parts [38](/cfr/46/part38.md) and [151](/cfr/46/part151.md) of this chapter respectively.
- (d) Underwater survey means the examination, while the vessel is afloat, of all accessible parts of the vessel's underwater body and all through-hull fittings.

## Notes

### Amendments

[CGD 84-024, 52 FR 39649, Oct. 23, 1987, as amended by CGD 84-024, 53 FR 32229, Aug. 24, 1988; CGD 95-028, 62 FR 51197, Sept. 30, 1997]

### Authority

Authority: 33 U.S.C. 1321(j); 46 U.S.C. 2103, 3205, 3306, 3307, 3703; 46 U.S.C. Chapter 701; E.O. 12234, 45 FR 58801, 3 CFR, 1980 Comp., p. 277; E.O. 12777, 56 FR 54757, 3 CFR, 1991 Comp., p. 351; DHS Delegation No. 00170.1, Revision No. 01.4. Section 31.10-21 also issued under the authority of Sect. 4109, Pub. L. 101-380, 104 Stat. 515.

### Source

Source: CGFR 65-50, 30 FR 16662, Dec. 30, 1965, unless otherwise noted.

### Amendments

[CGD 84-024, 52 FR 39649, Oct. 23, 1987, as amended by CGD 84-024, 53 FR 32229, Aug. 24, 1988; CGD 95-028, 62 FR 51197, Sept. 30, 1997]