# Floors.

**Citation:** 49 CFR 193.2159  
**Type / status:** regulation / historical  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 1999-10-01  
**Published:** Not stated

Floors of Class 2 and Class 3 impounding systems must, to the extent feasible—

(a) Slope away from the component or item impounded and to a sump basin installed under § 193.2171;

(b) Slope away from the nearest adjacent component;

(c) Drain surface waters from the floor at rates based on a storm 

## Document text

Floors of Class 2 and Class 3 impounding systems must, to the extent feasible—

(a) Slope away from the component or item impounded and to a sump basin installed under § 193.2171;

(b) Slope away from the nearest adjacent component;

(c) Drain surface waters from the floor at rates based on a storm of 10-year frequency and 1-hour duration and other natural water sources; and

(d) Be designed to minimize the wetted floor area.

## Provenance

- Official: Yes
- Source: <https://www.govinfo.gov/app/details/CFR-1999-title49-vol3/CFR-1999-title49-vol3-sec193-2159>
- Source ID: `govinfo-cfr`
- SHA-256: `4d3fda6b931425c1f469800162418bf3edfa10916cd0ff2c090cb235d690b77a`
- Retrieved: 2026-08-12T01:41:23.231Z
- Exported: 2026-08-23T09:22:48.498Z
- Document slug: `49-cfr-193-2159`

### Source metadata

```json
{
  "part": "193",
  "section": "193.2159",
  "subpart": "Subpart C—Design",
  "annualEdition": 1999,
  "revisedAsOf": "1999-10-01",
  "govInfoPackage": "CFR-1999-title49-vol3",
  "legalStatus": "official-annual-cfr-edition",
  "effectiveDateNote": null,
  "historicalAnchor": true,
  "historicalAnchorNote": "The section appears in an official annual CFR edition but is absent from the connected current eCFR corpus.",
  "jurisdiction": "US"
}
```