# Rules of regulatory construction.

**Citation:** 49 CFR 193.2009  
**Type / status:** regulation / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2026-08-18  
**Published:** Not stated

(a) As used in this part:

(1) Includes means including but not limited to;

(2) May means is permitted to or is authorized to;

(3) May not means is not permitted to or is not authorized to; and

(4) Shall or must is used in the mandatory and imperative sense.

(b) In this part:

(1) Words importin

## Document text

(a) As used in this part:

(1) Includes means including but not limited to;

(2) May means is permitted to or is authorized to;

(3) May not means is not permitted to or is not authorized to; and

(4) Shall or must is used in the mandatory and imperative sense.

(b) In this part:

(1) Words importing the singular include the plural; and

(2) Words importing the plural include the singular.

## Provenance

- Official: Yes
- Source: <https://www.ecfr.gov/on/2026-08-18/title-49/section-193.2009>
- Source ID: `ecfr`
- SHA-256: `1e0a51a4eecb263dd6ce3d391c67e74b3011f862d13f0f25005c6538c58b9b1b`
- Retrieved: 2026-08-20T05:54:35.243Z
- Exported: 2026-08-22T16:46:58.480Z
- Document slug: `49-cfr-193-2009`

### Source metadata

```json
{
  "cfrTitle": 49,
  "part": "193",
  "section": "193.2009",
  "subpart": "Subpart A—General",
  "corpusVersion": "2026-08-18",
  "jurisdiction": "US"
}
```