# -9 Compartments.

- **operation:** document
- **citation:** 49 CFR 178.255-9
- **title:** -9 Compartments.
- **source type:** regulation
- **agency:** Pipeline and Hazardous Materials Safety Administration
- **status:** current
- **official:** true
- **published on:** Not available
- **effective on:** 2026-08-18
- **summary:** (a) When the interior of the tank is divided into compartments, each compartment shall be designed, constructed and tested as a separate tank. Thickness of shell and compartment heads shall be determined on the basis of total tank capacity.

(b) [Reserved]
- **machine formats:** - **json:** https://regulus.evalyn.ai/document/49-cfr-178-255-9.json
- **markdown:** https://regulus.evalyn.ai/document/49-cfr-178-255-9.md
- **app url:** https://regulus.evalyn.ai/document/49-cfr-178-255-9
- **source url:** https://www.ecfr.gov/on/2026-08-18/title-49/section-178.255-9
**body:**

(a) When the interior of the tank is divided into compartments, each compartment shall be designed, constructed and tested as a separate tank. Thickness of shell and compartment heads shall be determined on the basis of total tank capacity.

(b) [Reserved]
- **truncated:** false
- **body characters:** 256