# -10 Postweld heat treatment.

**Citation:** 49 CFR 179.300-10  
**Type / status:** regulation / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2026-08-18  
**Published:** Not stated

After welding is complete, steel tanks and all attachments welded thereto, must be postweld heat treated as a unit in compliance with the requirements of AAR Specifications for Tank Cars, appendix W (IBR, see § 171.7 of this subchapter).

[68 FR 75763, Dec. 31, 2003]

## Document text

After welding is complete, steel tanks and all attachments welded thereto, must be postweld heat treated as a unit in compliance with the requirements of AAR Specifications for Tank Cars, appendix W (IBR, see § 171.7 of this subchapter).

[68 FR 75763, Dec. 31, 2003]

## Provenance

- Official: Yes
- Source: <https://www.ecfr.gov/on/2026-08-18/title-49/section-179.300-10>
- Source ID: `ecfr`
- SHA-256: `3df7d682a5fcd523ea381b09bfcffc834ab9629f2e2ecc0bb65387251784c1f8`
- Retrieved: 2026-08-20T05:46:20.606Z
- Exported: 2026-08-23T20:13:11.379Z
- Document slug: `49-cfr-179-300-10`

### Source metadata

```json
{
  "cfrTitle": 49,
  "part": "179",
  "section": "179.300-10",
  "subpart": "Subpart E—Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW)",
  "corpusVersion": "2026-08-18",
  "jurisdiction": "US"
}
```