46 CFR § 42.20-60 - Deduction for superstructures and trunks.

---
identifier: "/us/cfr/t46/s42.20-60"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 42.20-60 - Deduction for superstructures and trunks."
title_number: 46
title_name: "Shipping"
section_number: "42.20-60"
section_name: "Deduction for superstructures and trunks."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "E"
subchapter_name: "LOAD LINES"
part_number: "42"
part_name: "DOMESTIC AND FOREIGN VOYAGES BY SEA"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 5101-5116; Department of Homeland Security Delegation No. 00170.1, Revision No. 01.4; section 42.01-5 also issued under the authority of 44 U.S.C. 3507."
cfr_part: "42"
---


# 42.20-60 Deduction for superstructures and trunks.

(a) Where the effective length of superstructures and trunks is 1.0*L,* the deduction from the freeboard shall be 14 inches at 79 feet length of vessel, 34 inches at 279 feet length, and 42 inches at 400 feet length and above; deductions at intermediate lengths shall be obtained by linear interpolation.

(b) Where the total effective length of superstructures and trunks is less than 1.0*L* the deduction shall be a percentage obtained from table 42.20-60(b)(1) or table 42.20-60(b)(2):

Table 42.20-60(**b**)(1)—Percentage of Deduction For Type “A” Vessels

|  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Percentage of deduction for all types of superstructures | 0 | 7 | 14 | 21 | 31 | 41 | 52 | 63 | 75.3 | 87.7 | 100 |
| Percentages at intermediate lengths of superstructures and trunks shall be obtained by linear interpolation. |  |  |  |  |  |  |  |  |  |  |  |

Table 42.20-60(**b**)(2)—Percentage of Deduction for Type “B” Vessels

[**Percentage of deduction** ]

|  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Vessels with forecastle and without detached bridge | I | 0 | 5 | 10 | 15 | 23.5 | 32 | 46 | 63 | 75.3 | 87.7 | 100 |
| Vessels with forecastle and detached bridge | II | 0 | 6.3 | 12.7 | 19 | 27.5 | 36 | 46 | 63 | 75.3 | 87.7 | 100 |
| Percentages at intermediate lengths of superstructures and trunks shall be obtained by linear interpolation. |  |  |  |  |  |  |  |  |  |  |  |  |

(c) For vessels of Type “B”:

(1) Where the effective length of a bridge is less than 0.2*L,* the percentages shall be obtained by linear interpolation between lines I and II;

(2) Where the effective length of a forecastle is more than 0.4*L,* the percentages shall be obtained from line II; and,

(3) Where the effective length of a forecastle is less than 0.07*L,* the percentages in table 42.20-60(b)(2) of this paragraph shall be reduced by:

5(0.07*L*−*f*)/0.07*L*

*L* is the length of vessel as defined in § 42.13-15(a),

*f* is the effective length of the forecastle.

[CGFR 68-60, 33 FR 10065, July 12, 1968, as amended by CGFR 68-126, 34 FR 9015, June 5, 1969; USCG-2014-0688, 79 FR 58280, Sept. 29, 2014]