# 4D, 4DA, 4DS — How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested

For 4D, 4DA, 4DS, test or inspection is Periodic requalification; interval is 5; minimum test pressure is 2 times service pressure; regulation section is 49 CFR § 180.209, recorded from its source on 2026-08-06.

- **Container specification:** 4D, 4DA, 4DS _(verified: appears in the quote below)_
- **Test or inspection:** Periodic requalification _(our reading, not quoted from the source)_
- **Interval:** 5. _(verified: appears in the quote below)_
- **Minimum test pressure:** 2 times service pressure _(verified: appears in the quote below)_
- **Regulation section:** 49 CFR § 180.209 _(verified: appears in the quote below)_

## What the source says

> 4D, 4DA, 4DS | 2 times service pressure | 5.

## Source

- https://www.law.cornell.edu/cfr/text/49/180.209

Last verified: 2026-08-06. Review by: 2027-08-06.
Part of [How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested](https://referencesource.org/hazmat-container-retest-intervals/).