46 CFR § 128.450 - Liquid-mud systems.

---
identifier: "/us/cfr/t46/s128.450"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 128.450 - Liquid-mud systems."
title_number: 46
title_name: "Shipping"
section_number: "128.450"
section_name: "Liquid-mud systems."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "L"
subchapter_name: "OFFSHORE SUPPLY VESSELS"
part_number: "128"
part_name: "MARINE ENGINEERING: EQUIPMENT AND SYSTEMS"
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; sec. 617, Pub. L. 111-281, 124 Stat. 2905; Department of Homeland Security Delegation No. 0170.1."
regulatory_source: "CGD 82-004 and CGD 86-074, 62 FR 49331, Sept. 19, 1997, unless otherwise noted."
cfr_part: "128"
---


# 128.450 Liquid-mud systems.

(a) Liquid-mud piping systems may use resiliently seated valves of Category A to comply with §§ 56.20-15 and 56.50-60 of this chapter.

(b) Tanks for oil-based liquid mud must be fitted with tank vents equipped with flame screens. Vents must not discharge to the interior of the vessel.