# Special placarding provisions: Rail.

**Citation:** 49 CFR 172.510  
**Type / status:** regulation / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2026-08-18  
**Published:** Not stated

(a) White square background. The following must have the specified placards placed on a white square background, as described in § 172.527:

(1) Division 1.1 and 1.2 (explosive) materials which require EXPLOSIVES 1.1 or EXPLOSIVES 1.2 placards affixed to the rail car;

(2) Materials classed in Divis

## Document text

(a) White square background. The following must have the specified placards placed on a white square background, as described in § 172.527:

(1) Division 1.1 and 1.2 (explosive) materials which require EXPLOSIVES 1.1 or EXPLOSIVES 1.2 placards affixed to the rail car;

(2) Materials classed in Division 2.3 Hazard Zone A or 6.1 Packing Group I Hazard Zone A which require POISON GAS or POISON placards affixed to the rail car, including tank cars containing only a residue of the material; and

(3) Class DOT 113 tank cars used to transport a Division 2.1 (flammable gas) material, including tank cars containing only a residue of the material.

(b) Chemical ammunition. Each rail car containing Division 1.1 or 1.2 (explosive) ammunition which also meets the definition of a material poisonous by inhalation (see § 171.8 of this subchapter) must be placarded EXPLOSIVES 1.1 or EXPLOSIVES 1.2 and POISON GAS or POISON INHALATION HAZARD.

[Amdt. 172-29, 41 FR 15996, Apr. 15, 1976, as amended by Amdt. 172-103, 51 FR 5971, Feb. 18, 1986; Amdt. 172-110, 52 FR 29528, Aug. 10, 1987; Amdt. 172-111, 52 FR 36671, Sept. 30, 1987; Amdt. 172-123, 55 FR 52601, Dec. 21, 1990; 56 FR 66260, Dec. 20, 1991; 57 FR 45460, Oct. 1, 1992; Amdt. 172-248, 61 FR 28676, June 5, 1996; Amdt. 172-151, 62 FR 1231, Jan. 8, 1997; 62 FR 39398, July 22, 1997]

## Provenance

- Official: Yes
- Source: <https://www.ecfr.gov/on/2026-08-18/title-49/section-172.510>
- Source ID: `ecfr`
- SHA-256: `6f0b137b0980b0f6940ac3d60bbf1cdd501ff062f09443c1fc70f58d3b7367f8`
- Retrieved: 2026-08-20T05:45:59.130Z
- Exported: 2026-08-23T16:09:05.260Z
- Document slug: `49-cfr-172-510`

### Source metadata

```json
{
  "cfrTitle": 49,
  "part": "172",
  "section": "172.510",
  "subpart": "Subpart F—Placarding",
  "corpusVersion": "2026-08-18",
  "jurisdiction": "US"
}
```