A Cargo Tank Past Its 180.407 Test May Not Be Filled. The Table Names the Year.

The Situation

A service tech is asked to load a specification cargo tank because 'it ran last week.' 49 CFR 180.407(a)(1) says a cargo tank constructed in accordance with a DOT specification for which a test or inspection specified in this section has become due may not be filled and offered for transportation or transported until the test or inspection has been successfully completed. The paragraph does not apply to any cargo tank filled prior to the test or inspection due date.

The interval is in the table under 180.407(c), not in a shop saying.

The Facts

The compliance table under 180.407(c) is the calendar. External visual inspection, all other cargo tanks: interval period after first test, 1 year. Internal visual inspection, all other cargo tanks except MC 338: 5 years. Leakage test, all other cargo tanks except MC 338: 1 year. Pressure test, all other cargo tanks: 5 years.

A propane-specific row sits in that table. MC 331 cargo tanks less than 3,500 gallons water capacity in dedicated propane service constructed of nonquenched and tempered NQT SA-612 steel: 10 years for internal visual and 10 years for pressure test, with Note 5. That row is narrow. It is not a blanket 10-year holiday for every bobtail in the yard.

Leakage-test pressure for dedicated LPG is also numbered. 180.407(h)(1)(ii) says an MC 330 or MC 331 cargo tank in dedicated liquefied petroleum gas service may be leakage tested at not less than 414 kPa (60 psig). Test pressure must be maintained for at least 5 minutes. Cargo tanks in liquefied compressed gas service must be externally inspected for leaks during the leakage test.

Out-of-service is its own trip. 180.407(b)(3) says a cargo tank that has been out of hazardous materials transportation service for a period of one year or more must be pressure tested in accordance with 180.407(g) prior to further use. A parked spare that sat through last winter is not 'fine because it used to be in date.'

Damage does not wait for the anniversary. 180.407(b)(1) requires test and inspection if the cargo tank shows dents, cuts, gouges, corroded or abraded areas, leakage, or any other condition that might render it unsafe. 180.407(b)(2) requires a pressure test if the tank has sustained damage that may adversely affect lading retention.

Who may do the work is in 180.407(a)(3): a person witnessing or performing a test or inspection specified in this section must meet the minimum qualifications prescribed in 180.409. Passing tanks are marked under 180.415. Failing tanks are repaired and retested under 180.413, or removed from hazardous materials service with the specification plate removed, obliterated, or covered.

MC 330 and MC 331 tanks used for LPG that are constructed of quenched and tempered steel under Part UHT, or other than Q&T without postweld heat treatment in the named corrosive services, have a wet fluorescent magnetic particle internal inspection immediately prior to and in conjunction with the pressure test, per 180.407(g)(3). The rule applies that magnetic-particle requirement to MC 330 and MC 331 Q&T tanks used for the transportation of liquefied petroleum gas.

This section is cargo tanks. It is not the cylinder table in 180.209, and it is not a stationary ASME installation rule. A service tech who mixes those three will quote the wrong interval on the wrong vessel.

Business Impact

Loading a cargo tank past a due 180.407 test is a fill the HMR has already closed. The 1-year external visual and 1-year leakage test are the ones a busy shop misses. The 5-year pressure test is the one a parked spare misses after a year off the road.

Dedicated LPG leakage testing at not less than 60 psig is a number the shop can set on the gauge. It is not a reason to skip the 5-minute hold.

Key Takeaways

• 49 CFR 180.407(a)(1) says a specification cargo tank past a due test may not be filled until the test is done.
• External visual and leakage tests are 1 year for all other cargo tanks; pressure test is 5 years.
• An MC 330 or MC 331 in dedicated LPG service may be leakage tested at not less than 60 psig.
• A cargo tank out of hazardous materials service for one year or more needs a pressure test before further use.

Action Steps

1. 1.List every specification cargo tank and write the last external visual, leakage, internal visual, and pressure-test dates against the 180.407(c) table.
2. 2.Park any tank whose listed test is due. Do not fill it.
3. 3.Set the dedicated LPG leakage-test procedure at not less than 60 psig with a 5-minute hold.
4. 4.Pressure-test any cargo tank that has been out of hazardous materials service for one year or more before it returns.

Competitive Advantage

A shop that can point to 180.407(c) dates on every tank will load on Monday. A shop that loads on memory will meet the first sentence of 180.407(a)(1) on a scale ticket.