46 CFR § 45.31 - Deck line.

---
identifier: "/us/cfr/t46/s45.31"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 45.31 - Deck line."
title_number: 46
title_name: "Shipping"
section_number: "45.31"
section_name: "Deck line."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "E"
subchapter_name: "LOAD LINES"
part_number: "45"
part_name: "GREAT LAKES LOAD LINES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 5104, 5108; Department of Homeland Security Delegation No. 0170.1."
regulatory_source: "CGD 73-49R, 38 FR 12290, May 10, 1973, unless otherwise noted."
cfr_part: "45"
---


# 45.31 Deck line.

(a) Each vessel must be marked with a deck line on the outer surface of the shell on each side of the vessel with the upper edge of the line passing through the point where the upper surface of the freeboard deck intersects the outer surface of the shell or if the summer freeboard is correspondingly adjusted under § 45.57, the deck line may be placed above or below the freeboard deck. Figure 1 illustrates the deck line markings.

(b) Each deck line must be at least 12-inches long and 1-inch wide.