DOT Tank Inspections & Tests

V - External Visual Inspection - Annual Test
K - Leakage Test - Annual Inspection
I - Internal Visual Inspection - Five Year Test
P - Pressure Test - Five Year Test
T - Thickness Test - Two Year Test
UC - Upper Coupler Inspection - Five Year Test

COMPLIANCE DATES - INSPECTIONS AND TEST UNDER § 180.407(C)

Test or inspection (cargo tank specification, configuration, and service)

Date by which first test must be completed (see note 1)

Interval period after first test

External Visual Inspection:

All cargo tanks designed to be loaded by vacuum with full opening rear heads.

All other cargo tanks.

September 1, 1991

6 Months

1 Year

Internal Visual Inspection:

All insulated cargo tanks, except MC 330, MC 331, MC 338 (see Note 4).

All cargo tanks transporting lading corrosive to the tank

All other cargo tanks, except MC 338

September 1, 1991

September 1, 1995

1 Year

5 Years

Lining Inspection:

All lined cargo tanks transporting lading corrosive to the tank

September 1, 1991

1 Year

Leakage Test:

MC 330 and MC 331 cargo tanks in chlorine service

All other cargo tanks except MC 338

September 1, 1991

2 Years

1 Year

Pressure Test: (Hydrostatic or pneumatic) (See Notes 2 and 3)

All cargo tanks which are insulated with no manhole or insulated and lined, except MC 338.

All cargo tanks designed to be loaded by vacuum with full opening rear heads.

MC 330 and MC 331 cargo tanks in chlorine service

All other cargo tanks

September 1, 1991

September 1, 1992

September 1, 1995

1 Year

2 Years

5 Years

Thickness Test:

All unlined cargo tanks transporting material corrosive to the tank, except MC 338.

September 1, 1992

2 Years

NOTE 1: If a cargo tank is subject to an applicable inspection or test requirement under the regulations in effect on December 30, 1990, and the due date (as specified by a requirement in effect on December 30, 1990) for completing the required inspection or test occurs before the compliance date listed in table I, the earlier date applies.
NOTE 2: Pressure testing is not required for MC 330 and MC 331 cargo tanks in dedicated sodium metal service.
NOTE 3: Pressure testing is not required for uninsulated lined cargo tanks, with a design pressure or MAWP 15 psig or less, which receive an external visual inspection and lining inspection at least once each year.
NOTE 4: Insulated cargo tanks equipped with manholes or inspection openings may perform either an internal visual inspection in conjunction with the external visual inspection or a hydrostatic or pneumatic pressure-test of the cargo tank.