46 CFR § 172.100 - Watertight integrity.

---
identifier: "/us/cfr/t46/s172.100"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 172.100 - Watertight integrity."
title_number: 46
title_name: "Shipping"
section_number: "172.100"
section_name: "Watertight integrity."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "S"
subchapter_name: "SUBDIVISION AND STABILITY"
part_number: "172"
part_name: "SPECIAL RULES PERTAINING TO BULK CARGOES"
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. 3306, 3703, 5115; E.O. 12234, 45 FR 58801, 3 CFR, 1980 Comp., p. 277; DHS Delegation 00170.1, Revision No. 01.2."
regulatory_source: "CGD 79-023, 48 FR 51040, Nov. 4, 1983, unless otherwise noted."
cfr_part: "172"
---


# 172.100 Watertight integrity.

(a) Except as provided in paragraph (b) of this section, each Type I or II hopper barge hull must have a weathertight weather deck.

(b) If a Type I or II barge hull has an open hopper, the fully loaded barge must be shown by design calculations to have at least 2 inches (50 mm) of positive GM when the hopper space is flooded to the height of the weather deck.

(c) When doing the calculations required by this section, credit may be given for the buoyancy of the immersed portion of cargo tanks if the tank securing devices are shown by design calculations to be strong enough to hold the tanks in place when they are subjected to the buoyant forces resulting from the water in the hopper.