# Maximum allowable operating speed.

**Citation:** 49 CFR 174.86  
**Type / status:** regulation / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2026-08-18  
**Published:** Not stated

(a) For molten metals and molten glass shipped in packagings other than those prescribed in § 173.247 of this subchapter, the maximum allowable operating speed may not exceed 24 km/hour (15 mph) for shipments by rail.

(b) For trains transporting any loaded, placarded tank cars containing a material

## Document text

(a) For molten metals and molten glass shipped in packagings other than those prescribed in § 173.247 of this subchapter, the maximum allowable operating speed may not exceed 24 km/hour (15 mph) for shipments by rail.

(b) For trains transporting any loaded, placarded tank cars containing a material poisonous by inhalation, the maximum allowable operating speed may not exceed 80.5 km/hour (50 mph) for shipments by rail.

[74 FR 1801, Jan. 13, 2009]

## Provenance

- Official: Yes
- Source: <https://www.ecfr.gov/on/2026-08-18/title-49/section-174.86>
- Source ID: `ecfr`
- SHA-256: `028539ce26485e0278494720225bc7938cdf4a1365c18cf3923f7d999b10c56d`
- Retrieved: 2026-08-20T05:46:04.619Z
- Exported: 2026-08-24T03:43:07.342Z
- Document slug: `49-cfr-174-86`

### Source metadata

```json
{
  "cfrTitle": 49,
  "part": "174",
  "section": "174.86",
  "subpart": "Subpart D—Handling of Placarded Rail Cars, Transport Vehicles and Freight Containers",
  "corpusVersion": "2026-08-18",
  "jurisdiction": "US"
}
```