46 CFR § 108.439 - Quantity of CO for protection of spaces.

---
identifier: "/us/cfr/t46/s108.439"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 108.439 - Quantity of CO for protection of spaces."
title_number: 46
title_name: "Shipping"
section_number: "108.439"
section_name: "Quantity of CO for protection of spaces."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "I-A"
subchapter_name: "A—MOBILE OFFSHORE DRILLING UNITS"
part_number: "108"
part_name: "DESIGN AND EQUIPMENT"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "43 U.S.C. 1333; 46 U.S.C. 3102, 3306; DHS Delegation No. 00170.1, Revision No. 01.4."
regulatory_source: "CGD 73-251, 43 FR 56808, Dec. 4, 1978, unless otherwise noted."
cfr_part: "108"
---


# 108.439 Quantity of CO for protection of spaces.

(a) The number of pounds of CO<sub>2</sub> required to protect a space must be equal to the gross volume of the space divided by the appropriate factor from Table 108.439.

(b) If a machinery space includes a casing, the gross volume of the space may be calculated using the reductions allowed in 46 CFR 95.10-5(e).

(c) If fuel can drain from a space to an adjacent space or if two spaces are not entirely separate, the requirements for both spaces must be used to determine the amount of CO<sub>2</sub> to be provided and the CO<sub>2</sub> system must be arranged to discharge into both spaces simultaneously.

Table 108.439—**CO** **Supply Factors**

[Gross volume of space in cubic feet]

| Over | Not over | Factor |
| --- | --- | --- |
| 0 | 500 | 15 |
| 500 | 1,600 | 16 |
| 1,600 | 4,500 | 18 |
| 4,500 | 50,000 | 20 |
| 50,000 |  | 22 |