# DOT-3AL Cylinders Made of Aluminum Alloy 6351-T6 — How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested

For DOT-3AL Cylinders Made of Aluminum Alloy 6351-T6, test or inspection is Eddy current examination combined with visual inspection; interval is 5; regulation section is 49 CFR § 180.209, recorded from its source on 2026-08-06.

- **Container specification:** DOT-3AL Cylinders Made of Aluminum Alloy 6351-T6 _(verified: appears in the quote below)_
- **Test or inspection:** Eddy current examination combined with visual inspection _(our reading, not quoted from the source)_
- **Interval:** 5 _(verified: appears in the quote below)_
- **Regulation section:** 49 CFR § 180.209 _(verified: appears in the quote below)_

## What the source says

> Table 4 to Paragraph (m)—Requalification and Inspection of DOT-3AL Cylinders Made of Aluminum Alloy 6351-T6 Requalification requirement | Examination procedure 1 | Sustained Load Cracking Condemnation Criteria 2 | Requalification period (years) | Eddy current examination combined with visual inspection | Eddy current—In accordance with Appendix C of this part Visual inspection—In accordance with CGA Pamphlet C-6.1 (IBR; see <https://www.law.cornell.edu/cfr/text/49/171.7> § 171.7 of this subchapter) | Any crack in the neck or shoulder of 2 thread lengths or more | 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/).