USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #20-0092

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Public Utilities Commission of Ohio Transportation Department

Individual Name: Tom Forbes

Location State: OH Country: US

View the Interpretation Document

Response text:

February 8, 2021

Tom Forbes
Public Utilities Commission of Ohio
Transportation Department
180 East Broad St, 4th floor
Columbus, OH  43215

Reference No. 20-0092

Dear Mr. Forbes:

This letter is in response to your November 30, 2020, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to a vinyl wrapped cargo tank motor vehicle (CTMV). Specifically, you ask about the inspection requirements pertaining to a Specification MC-331 CTMV (i.e., a bobtail metered delivery truck) that is fitted with a vinyl wrap covering significant portions of the sides of the cargo tank, thus precluding the performance of external visual inspections as required in § 180.407. You also state that the CTMV is not equipped with a manhole to allow for an internal visual inspection, as is required when external visual inspections are not practicable. Finally, you ask whether an annual pressure test (e.g., hydrostatic or pneumatic) is required in lieu of an external visual inspection when neither an external—or substitute internal—visual inspection is possible.

The answer is yes. As required by § 180.407(c), an inspector must complete the external visual inspection annually, except for on a cargo tank designed to be loaded by vacuum with full opening rear heads. If the external visual inspection is prevented because any part of the cargo tank wall is externally lined, coated, or otherwise designed to prevent an external visual inspection, those areas of the cargo tank must be internally inspected. If the internal visual inspection is prevented because the cargo tank is lined, coated, or otherwise designed to prevent access for internal visual inspection, the cargo tank must be hydrostatically or pneumatically tested in accordance with § 180.407(g)(1)(iv)(see § 180.407(d)(1)). Therefore, the bobtail metered delivery truck you described must be annually pressure tested because the vinyl wrap prevents a complete external visual inspection, and the lack of a manhole prevents an internal visual inspection.

I hope this information is helpful. Please contact us if we can be of further assistance.


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

180.407, 180.407(c), 180.407(g)(1)(iv), 180.407(d)(1)

Regulation Sections

Section Subject
180.407 Requirements for test and inspection of specification cargo tanks