Reference Source

DOT Specifications 4B, 4BA, 4BW, or 4E

For DOT Specifications 4B, 4BA, 4BW, or 4E, test or inspection is volumetric expansion testing; interval is every 12 years instead of every 5 years; condition or service qualifier is protected externally by a suitable corrosion-resistant coating and used exclusively for non-corrosive gas that is commercially free from corroding components; regulation section is 49 CFR § 180.209, recorded from its source on 2026-08-06.

Container specification
DOT Specifications 4B, 4BA, 4BW, or 4E verified
Test or inspection
volumetric expansion testing our reading
Interval
every 12 years instead of every 5 years verified
Condition or service qualifier
protected externally by a suitable corrosion-resistant coating and used exclusively for non-corrosive gas that is commercially free from corroding components verified
Regulation section
49 CFR § 180.209 verified
Sourcelaw.cornell.edu
Verified2026-08-06
Review by2027-08-06
DatasetHow often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested

Values marked our reading are our classification of what the source says — the source does not print them in those words. The quote below is the evidence for each one; judge it yourself.

What the source says

A cylinder made in conformance with DOT Specifications 4B, 4BA, 4BW, or 4E protected externally by a suitable corrosion-resistant coating and used exclusively for non-corrosive gas that is commercially free from corroding components may be requalified by volumetric expansion testing every 12 years instead of every 5 years.

law.cornell.edu, retrieved 2026-08-06

Source

Last verified against source: 2026-08-06. Due for re-check by 2027-08-06. This page as Markdown · OKF bundle · full dataset as JSON.