40 CFR § 139.23 - Inert gas systems.

---
identifier: "/us/cfr/t40/s139.23"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 139.23 - Inert gas systems."
title_number: 40
title_name: "Protection of Environment"
section_number: "139.23"
section_name: "Inert gas systems."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "D"
subchapter_name: "WATER PROGRAMS"
part_number: "139"
part_name: "DISCHARGES INCIDENTAL TO THE NORMAL OPERATION OF VESSELS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "33 U.S.C. 1251"
regulatory_source: "89 FR 82131, Oct. 9, 2024, unless otherwise noted."
cfr_part: "139"
---


# 139.23 Inert gas systems.

There are no additional discharge-specific requirements that apply to the discharge of washwater from an inert gas system and deck seal water when used as an integral part of that system.