A properly maintained specification cargo tank should outlast at least one truck chassis and can provide a long service life over a new set of wheels. The U.S. Department of Transportation recently issued an interpretation, which should help truck owners maintain compliance when making change-outs and doing remounts. 

The DOT designates minimum design and construction requirements for cargo tanks used to haul hazardous materials. Specification tank trucks must be constructed to the DOT specifications. 

The first step is to research whether you need a specification cargo tank for the products you will transport. If you know you will — or even might — need a spec tank, then, as the tank owner, you must ensure that all regulatory requirements are met. 

Next, make sure that the facility that will perform the work is registered as a manufacturer or assembler with the Federal Motor Carrier Safety Administration. If the facility does not understand the question, find another facility. 

Beyond the basic requirement that the facility be registered with FMCSA, the regulations governing a remount will vary depending on what work will be performed. The key factor will be how the existing tank will be attached to the chassis. 

The facility does not need to issue a new certificate of compliance or new specification plate if the work is performed:

1. With no structural change (modification) to the cargo tank.
2. In conformance with the cargo tank’s original specification for attachment to the chassis or the specification for attachment to the chassis in effect at the time of mounting.
3. Under the supervision of an inspector registered with the DOT. Note: In order to verify that the tank is attached according to the original specification of attachment, the facility performing the work will have to prove that it has access to the original specification paperwork. 

However, if the remounting will require welding to the cargo tank shell or change from the original means of mounting the tank to the chassis, the work will have to be approved via a certification from a Design Certifying Engineer and modifications to the cargo tank’s specification plate. 

The DOT regulations differentiate between a cargo tank manufacturer and assembler. Again, both facilities must be registered with the FMCSA. A facility may register as an assembler if no changes are made to the tank’s structure or design — such as through bolting — when mounting to a different chassis. A facility must register as a manufacturer if remounting results in changes to the tank’s structure or design. Remember, if any welding will be required to the tank shell, the facility must hold an R-Stamp issued by the National Board of Pressure Vessel Inspectors. 

Another issue in specification tank truck remounting is the bumper or rear-end protection device. If the new mounting will affect the cargo tank shell, a Design Certifying Engineer must certify that the device provides protection per the regulations. If you purchase a truck with a remounted specification tank, ensure the seller can verify that the bumper is in compliance. If the mounting does not affect the cargo tank shell, no DCE certification is required.

Whether you perform the remounting yourself, have the work performed by an outside service supplier, or purchase a remounted cargo tank, make sure to retain all documentation of the vehicle’s repair or modification while the vehicle is in service and for one year thereafter. 

For a copy of the recent Letter of Interpretation contact John Conley at concomm@atlanticbb.net. 

About the Author
John Conley is past president of National Tank Truck Carriers and former editor of Modern Bulk Transporter magazine. He is president of ConleyComm LLC in Chester, Md.