What does 49 CFR 180.411 (Acceptable results of tests and inspections) require?

Short answer

49 CFR 180.411 requires that cargo tanks meet specific standards for corrosion, dents, cuts, digs, and gouges, as well as weld or structural defects, leakage, relief valves, liner integrity, and pressure tests. The regulation sets out acceptable results for tests and inspections of cargo tanks.

The rule says

"The minimum thickness may not be less than that prescribed in the applicable specification." (49 CFR 180.411(a))

"For dents at welds or that include a weld, the maximum allowable depth is 1/2 inch." (49 CFR 180.411(b)(1))

"Any cargo tank with a weld defect such as a crack, pinhole, or incomplete fusion, or a structural defect must be taken out of hazardous materials service until repaired." (49 CFR 180.411(c))

In plain English

This regulation is about ensuring cargo tanks are safe for transporting hazardous materials. It sets out specific requirements for inspecting and testing tanks to make sure they can withstand the stresses of transport without leaking or failing. For example, if a tank has a dent near a weld, it can't be more than half an inch deep. If a tank has a weld defect or structural problem, it has to be taken out of service until it's fixed. Inspectors will check for these kinds of issues when they examine a tank, and if they find any problems, the tank can't be used until it's repaired.

What to do

• Ensure all cargo tanks are inspected and tested according to the requirements in 49 CFR 180.411.
• Check for corrosion, dents, cuts, digs, and gouges, and verify that the minimum thickness of the tank meets the applicable specification.
• Verify that any weld or structural defects are repaired before the tank is returned to service.
• Ensure that all relief valves are functioning properly and that any leaks are repaired before the tank is used.