46 CFR § 197.322 - Surface-supplied helmets and masks.

---
identifier: "/us/cfr/t46/s197.322"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 197.322 - Surface-supplied helmets and masks."
title_number: 46
title_name: "Shipping"
section_number: "197.322"
section_name: "Surface-supplied helmets and masks."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "V"
subchapter_name: "MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS"
part_number: "197"
part_name: "GENERAL PROVISIONS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "33 U.S.C. 1509; 43 U.S.C. 1333; 46 U.S.C. 3306, 3703, 6101; Department of Homeland Security Delegation No. 0170.1."
regulatory_source: "CGD 76-009, 43 FR 53683, Nov. 16, 1978, unless otherwise noted."
cfr_part: "197"
---


# 197.322 Surface-supplied helmets and masks.

(a) Each surface-supplied helmet or mask must have—

(1) A nonreturn valve at the attachment point between helmet or mask and umbilical that closes readily and positively;

(2) An exhaust valve; and

(3) A two-way voice communication system between the diver and the dive location or bell.

(b) Each surface-supplied air helmet or mask must—

(1) Ventilate at least 4.5 ACFM at any depth at which it is operated; or

(2) Be able to maintain the diver's inspired carbon dioxide partial pressure below 0.02 ATA when the diver is producing carbon dioxide at the rate of 1.6 standard liters per minute.