33 CFR § 183.110 - Definitions.

---
identifier: "/us/cfr/t33/s183.110"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "33 CFR § 183.110 - Definitions."
title_number: 33
title_name: "Navigation and Navigable Waters"
section_number: "183.110"
section_name: "Definitions."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "S"
subchapter_name: "BOATING SAFETY"
part_number: "183"
part_name: "BOATS AND ASSOCIATED EQUIPMENT"
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. 4302; Pub. L. 103-206, 107 Stat. 2439; and Department of Homeland Security Delegation No. 0170.1, para. II, (92)(b). Subpart E is also authorized by Pub. L. 114-120, 130 Stat. 27"
regulatory_source: "CGD 72-61R, 37 FR 15782, Aug. 4, 1972, unless otherwise noted."
cfr_part: "183"
---


# 183.110 Definitions.

For the purpose of this subpart:

*Bilge* means the area in the boat, below a height of 4 inches measured from the lowest point in the boat where liquid can collect when the boat is in its static floating position, except engine rooms.

*Connected* means allowing a flow of water in excess of one-quarter ounce per hour from the engine room bilge into any other compartment with a 12 inch head of water on the engine room side of the bulkhead.

*Engine room bilge* means the area in the engine room or a connected compartment below a height of 12 inches measured from the lowest point where liquid can collect in these compartments when the boat is in its static floating position.

*Engine room* means the compartment where a permanently installed gasoline or diesel engine is installed, including connected compartments.

*Open to atmosphere* means a compartment that has at least 15 square inches of open area directly exposed to the atmosphere for each cubic foot of net compartment volume.

*Sealed compartment* means an enclosure that can resist an exterior water level of 12 inches without seepage of more than one-quarter fluid ounce per hour.

[CGD 77-145, 43 FR 56858, Dec. 4, 1978, as amended by CGD 82-010, 48 FR 8273, Feb. 28, 1983; CGD 85-098, 52 FR 19728, May 27, 1987; CGD 96-026, 61 FR 33670, June 28, 1996; USCG-1999-5832, 64 FR 34716, June 29, 1999; USCG-1999-5151, 64 FR 67176, Dec. 1, 1999]