40 CFR § 1042.635 - National security exemption.

---
identifier: "/us/cfr/t40/s1042.635"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 1042.635 - National security exemption."
title_number: 40
title_name: "Protection of Environment"
section_number: "1042.635"
section_name: "National security exemption."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "U"
subchapter_name: "AIR POLLUTION CONTROLS"
part_number: "1042"
part_name: "CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401-7671q."
regulatory_source: "73 FR 37243, June 30, 2008, unless otherwise noted."
cfr_part: "1042"
---


# 1042.635 National security exemption.

Engines qualify for a national security exemption as described in 40 CFR 1068.225. This applies to both freshly manufactured and remanufactured engines.

[81 FR 74151, Oct. 25, 2016]