# IM or UN portable tank — How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested

For IM or UN portable tank, test or inspection is intermediate periodic inspection and test; interval is at least every 2.5 years following the initial inspection and the last 5 year periodic inspection and test; regulation section is 49 CFR § 180.605, recorded from its source on 2026-08-10.

- **Container specification:** IM or UN portable tank _(verified: appears in the quote below)_
- **Test or inspection:** intermediate periodic inspection and test _(our reading, not quoted from the source)_
- **Interval:** at least every 2.5 years following the initial inspection and the last 5 year periodic inspection and test _(verified: appears in the quote below)_
- **Regulation section:** 49 CFR § 180.605 _(verified: appears in the quote below)_

## What the source says

> Each IM or UN portable tank must be given an initial <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=eb4e796dbf95b89f84dd98bdb7243f5c&term_occur=999&term_src=Title:49:Subtitle:B:Chapter:I:Subchapter:C:Part:180:Subpart:G:180.605> inspection and test before being placed into service, a periodic inspection and test at least once every 5 years, and an intermediate periodic inspection and test at least every 2.5 years following the initial inspection and the last 5 year periodic inspection and test .

## Source

- https://www.law.cornell.edu/cfr/text/49/180.605

Last verified: 2026-08-10. Review by: 2027-08-10.
Part of [How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested](https://referencesource.org/hazmat-container-retest-intervals/).