---
kind: "section"
citation: "33 C.F.R. § 401.10"
title: "33"
number: "401.10"
heading: "Mooring lines."
url: "https://uscodex.org/cfr/33/401.10"
---

# §401.10. Mooring lines.

- (a) **Mooring lines shall—**
  - (1) Be of a uniform thickness throughout their length;
  - (2) Have a diameter not greater than 28 mm for wire line and not greater than 64 mm for approved synthetic lines;
  - (3) Be fitted with a hand spliced eye or Flemish type mechanical spliced eye of not less than 2.4 m long for wire lines and 1.8 m long spliced eye for approved synthetic lines;
  - (4) Have sufficient strength to check the vessel; and
  - (5) Be arranged so that they may be led to either side of the vessel as required.
  - (6) Be certified and a test certificate for each mooring line containing information on breaking strength, material type, elongation and diameter shall be available onboard for inspection.
- (b) Unless otherwise permitted by an officer, vessels greater than 200 m shall only use wire mooring lines with a breaking strength that complies with the minimum specifications set out in the table to this section shall be used for securing a vessel in lock chambers.
- (c) [Reserved]
- (d) **Notwithstanding paragraphs (a) through (c) of this section, nylon line is not permitted.**
- (e) Hand held synthetic lines if permitted by the Manager or Corporation shall meet the criteria in [paragraph (a)](#a) of this section and shall have a minimum length of not less than 65 meters.

## Notes

### Amendments

[39 FR 10900, Mar. 22, 1974, as amended at 47 FR 51121, Nov. 12, 1982; 48 FR 20691, May 9, 1983; 48 FR 22545, May 19, 1983; 61 FR 19551, May 2, 1996; 65 FR 52913, Aug. 31, 2000; 70 FR 12970, Mar. 17, 2005; 74 FR 18994, Apr. 27, 2009; 75 FR 10689, Mar. 9, 2010; 78 FR 16181, Mar. 14, 2013; 79 FR 12659, Mar. 6, 2014; 81 FR 13745, Mar. 15, 2016; 87 FR 12591, Mar. 7, 2022; 90 FR 1882, Jan. 10, 2025]

### Authority

Authority: 33 U.S.C. 983(a) and 984(a)(4), as amended; 49 CFR 1.101, unless otherwise noted.

### Source

Source: 39 FR 10900, Mar. 22, 1974, unless otherwise noted.

### Amendments

[39 FR 10900, Mar. 22, 1974, as amended at 47 FR 51121, Nov. 12, 1982; 48 FR 20691, May 9, 1983; 48 FR 22545, May 19, 1983; 61 FR 19551, May 2, 1996; 65 FR 52913, Aug. 31, 2000; 70 FR 12970, Mar. 17, 2005; 74 FR 18994, Apr. 27, 2009; 75 FR 10689, Mar. 9, 2010; 78 FR 16181, Mar. 14, 2013; 79 FR 12659, Mar. 6, 2014; 81 FR 13745, Mar. 15, 2016; 87 FR 12591, Mar. 7, 2022; 90 FR 1882, Jan. 10, 2025]