49 C.F.R. § 179.101-1
Individual specification requirements.
Cite as 49 C.F.R. § 179.101-1 (2026)
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 2
1
⁄
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]
- Cross-references to the CFR
- 171.7179.100179.103-2.