49 CFR § 173.140 - Class 9—Definitions.

---
identifier: "/us/cfr/t49/s173.140"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 173.140 - Class 9—Definitions."
title_number: 49
title_name: "Transportation"
section_number: "173.140"
section_name: "Class 9—Definitions."
chapter_name: "PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "C"
subchapter_name: "HAZARDOUS MATERIALS REGULATIONS"
part_number: "173"
part_name: "SHIPPERS—GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 5101-5128, 44701; 49 CFR 1.81, 1.96 and 1.97."
cfr_part: "173"
---


# 173.140 Class 9—Definitions.

For the purposes of this subchapter, *miscellaneous hazardous material* (Class 9) means a material which presents a hazard during transportation but which does not meet the definition of any other hazard class. This class includes:

(a) Any material which has an anesthetic, noxious or other similar property which could cause extreme annoyance or discomfort to a flight crew member so as to prevent the correct performance of assigned duties; or

(b) Any material that meets the definition in § 171.8 of this subchapter for an elevated temperature material, a hazardous substance, a hazardous waste, or a marine pollutant.

[Amdt. 173-224, 57 FR 45463, Oct. 1, 1992, as amended by Amdt. 173-231, 57 FR 52939, Nov. 5, 1992; Amdt. 173-233, 58 FR 33305, June 16, 1993]