49 CFR § 179.2 - Definitions and abbreviations.

---
identifier: "/us/cfr/t49/s179.2"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 179.2 - Definitions and abbreviations."
title_number: 49
title_name: "Transportation"
section_number: "179.2"
section_name: "Definitions and abbreviations."
chapter_name: "PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "C"
subchapter_name: "HAZARDOUS MATERIALS REGULATIONS"
part_number: "179"
part_name: "SPECIFICATIONS FOR TANK CARS"
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; 49 CFR 1.81 and 1.97."
regulatory_source: "29 FR 18995, Dec. 29, 1964, unless otherwise noted. Redesignated at 32 FR 5606, Apr. 5, 1967."
cfr_part: "179"
---


# 179.2 Definitions and abbreviations.

(a) The following apply in part 179:

(1) *AAR* means Association of American Railroads.

(2) *Approved* means approval by the AAR Tank Car Committee.

(3) *ASTM* means American Society for Testing and Materials.

(4) [Reserved]

(5) Definitions in part 173 of this chapter also apply.

(6) *F* means degrees Fahrenheit.

(7) *NGT* means National Gas Taper Threads.

(8) *NPT* means an American Standard Taper Pipe Thread conforming to the requirements of NBS Handbook H-28 (IBR, see § 171.7 of this subchapter).

(9) [Reserved]

(10) *Tank car facility* means an entity that manufactures, repairs, inspects, tests, qualifies, or maintains a tank car to ensure that the tank car conforms to this part and subpart F of part 180 of this subchapter, that alters the certificate of construction of the tank car, that ensures the continuing qualification of a tank car by performing a function prescribed in parts 179 or 180 of this subchapter, or that makes any representation indicating compliance with one or more of the requirements of parts 179 or 180 of this subchapter.

(11) *Tanks* means tank car tanks.

(b) [Reserved]

[29 FR 18995, Dec. 20, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179-10, 36 FR 21344, Nov. 6, 1971; Amdt. 179-50, 60 FR 49076, Sept. 21, 1995; Amdt. 179-50, 61 FR 33255, June 26, 1996; 63 FR 52850, Oct. 1, 1998; 66 FR 45186, 45390, Aug. 28, 2001; 68 fR 75759, Dec. 31, 2003]