# DOT 3A, 3AA, 3B, 4BA, or 4BW — How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested

For DOT 3A, 3AA, 3B, 4BA, or 4BW, test or inspection is Periodic requalification; interval is every 10 years instead of every five years; condition or service qualifier is used exclusively for methyl bromide; regulation section is 49 CFR § 180.209, recorded from its source on 2026-08-06.

- **Container specification:** DOT 3A, 3AA, 3B, 4BA, or 4BW _(verified: appears in the quote below)_
- **Test or inspection:** Periodic requalification _(our reading, not quoted from the source)_
- **Interval:** every 10 years instead of every five years _(verified: appears in the quote below)_
- **Condition or service qualifier:** used exclusively for methyl bromide _(verified: appears in the quote below)_
- **Regulation section:** 49 CFR § 180.209 _(verified: appears in the quote below)_

## What the source says

> A cylinder conforming to specification DOT 3A, 3AA, 3B, 4BA, or 4BW having a service pressure of 300 psig or less and used exclusively for methyl bromide, <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=d496477211992c9631bc3d13ef381c7e&term_occur=999&term_src=Title:49:Subtitle:B:Chapter:I:Subchapter:C:Part:180:Subpart:C:180.209> liquid ; mixtures of methyl bromide and ethylene dibromide, liquid ; mixtures of methyl bromide and chlorpicrin, liquid ; mixtures of methyl bromide and petroleum solvents, liquid ; or methyl bromide and nonflammable, nonliquefied compressed gas mixtures , liquid ; commercially free of corroding components, and protected externally by a suitable corrosion resistant coating (such as galvanizing or painting) and internally by a suitable corrosion resistant lining (such as galvanizing) may be tested every 10 years instead of every five years, provided a visual internal and external examination of the cylinder is conducted every five years in accordance with CGA Pamphlet C-6.

## 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/).