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CFR > Title 14 - Aeronautics and Space > CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION > SUBCHAPTER C—AIRCRAFT (parts 21 to 50) > PART 25—AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES > SUBPART D—Design and Construction (§25.601 to §25.899) > 25.833—Combustion heating systems.
25.833—Combustion heating systems.
Combustion heaters must be approved.