# -1 Individual specification requirements.

**Citation:** 49 CFR 179.101-1  
**Type / status:** regulation / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2026-08-18  
**Published:** Not stated

In addition to § 179.100, the individual specification requirements are as follows:

DOT specification Insulation Bursting pressure (psig) Minimum plate thickness (inches) Test pressure (psig) Manway cover thickness Bottom outlet Bottom washout Reference(179.***) 105A100ALW Yes 500 5/8 100 2 2 1/2 N

## Document text

In addition to § 179.100, the individual specification requirements are as follows:

DOT specification Insulation Bursting pressure (psig) Minimum plate thickness (inches) Test pressure (psig) Manway cover thickness Bottom outlet Bottom washout Reference(179.***) 105A100ALW Yes 500 5/8 100 2 2 1/2 No No 105A200ALW Yes 500 5/8 200 2 2 1/2 No No 105A300ALW Yes 750 5/8 300 2 2 5/8 No No 105A100W Yes 500 3 9/16 100 2 1/4 No No 105A200W Yes 500 3 9/16 200 2 1/4 No No 105A300W Yes 750 1 11/16 300 7 2 1/4 No No 105A400W Yes 1,000 1 11/16 400 7 2 1/4 No No 105A500W Yes 1,250 1 11/16 500 2 1/4 No No 102-1, 102-2 105A600W Yes 1,500 1 11/16 600 2 1/4 No No 102-4, 102-17 109A100ALW Optional 500 5/8 100 2 2 1/2 No Optional 109A200ALW Optional 500 5/8 200 2 2 1/2 No Optional 109A300ALW Optional 750 5/8 300 2 2 5/8 No Optional 109A300W Optional 500 1 11/16 300 2 1/4 No Optional 112A200W Optional 4 500 3 5 9/16 200 2 1/4 No No 112A340W Optional 4 850 1 11/16 340 2 1/4 No No 112A400W Optional 4 1,000 1 11/16 400 2 1/4 No No 112A500W Optional 4 1,250 1 11/16 500 2 1/4 No No 114A340W Optional 4 850 1 11/16 340 6 Optional Optional 103 114A400W Optional 4 1,000 1 11/16 400 6 Optional Optional 103 120A200ALW Yes 500 5/8 200 2 2 1/2 Optional Optional 103 120A100W Yes 500 3 9/16 100 2 1/4 Optional Optional 103 120A200W Yes 500 3 9/16 200 2 1/4 Optional Optional 103 120A300W Yes 750 1 11/16 300 2 1/4 Optional Optional 103 120A400W Yes 1,000 1 11/16 400 2 1/4 Optional Optional 103 120A500W Yes 1,250 1 11/16 500 2 1/4 Optional Optional 103 1 When steel of 65,000 to 81,000 p.s.i. minimum tensile strength is used, the thickness of plates shall be not less than 5⁄8 inch, and when steel of 81,000 p.s.i. minimum tensile strength is used, the minimum thickness of plate shall be not less than 9⁄16 inch. 2 When approved material other than aluminum alloys are used, the thickness shall be not less than 21⁄4 inches. 3 When steel of 65,000 p.s.i. minimum tensile strength is used, minimum thickness of plates shall be not less than 1⁄2 inch. 4 Tank cars not equipped with a thermal protection or an insulation system used for the transportation of a Class 2 (compressed gas) material must have at least the upper two-thirds of the exterior of the tank, including manway nozzle and all appurtenances in contact with this area, finished with a reflective coat of white paint. 5 For inside diameter of 87 inches or less, the thickness of plates shall be not less than 1⁄2 inch. 6 See AAR Specifications for Tank Cars, appendix E, E4.01 (IBR, see § 171.7 of this subchapter), and § 179.103-2. 7 When the use of nickel is required by the lading, the thickness shall not be less than two inches.

[Amdt. 179-52, 61 FR 28679, June 5, 1996, as amended at 66 FR 45390, Aug. 28, 2001; 68 FR 75760, Dec. 31, 2003]

## Provenance

- Official: Yes
- Source: <https://www.ecfr.gov/on/2026-08-18/title-49/section-179.101-1>
- Source ID: `ecfr`
- SHA-256: `46dd8034fb7c9ee895a6a00f68475fdeb871a0f6dfadf84ad09cfb3b55a017c5`
- Retrieved: 2026-08-20T05:46:20.606Z
- Exported: 2026-08-25T16:32:10.374Z
- Document slug: `49-cfr-179-101-1`

### Source metadata

```json
{
  "cfrTitle": 49,
  "part": "179",
  "section": "179.101-1",
  "subpart": "Subpart C—Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120)",
  "corpusVersion": "2026-08-18",
  "jurisdiction": "US"
}
```