46 CFR § 143.500 - Applicability.

---
identifier: "/us/cfr/t46/s143.500"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 143.500 - Applicability."
title_number: 46
title_name: "Shipping"
section_number: "143.500"
section_name: "Applicability."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "M"
subchapter_name: "TOWING VESSELS"
part_number: "143"
part_name: "MACHINERY AND ELECTRICAL SYSTEMS AND EQUIPMENT"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 3103, 3301, 3306, 3308, 3316, 8104, 8904; 33 CFR 1.05; DHS Delegation No. 0170.1."
regulatory_source: "USCG-2006-24412, 81 FR 40101, June 20, 2016, unless otherwise noted."
cfr_part: "143"
---


# 143.500 Applicability.

(a) This subpart applies to a new towing vessel, as defined in § 136.110 of this subchapter, unless it is an excepted vessel.

(b) Machinery or electrical systems of a novel design, unusual form, or special material must meet section § 143.210.

(c) Unless otherwise noted in §§ 143.515 and 143.520, new towing vessels must also meet the requirements of subpart B of this part.