This page explains the requirements for structural inspections of TC 423 highway tank trailers in accordance with CSA B620. Highway tank trucks are not subject to this requirement.
This page does not change, create, or alter the Transportation of Dangerous Goods (TDG) Regulations.
On this page
- Structural inspections authorization requirement
- Applying to perform a structural inspection
- Structural inspections as per Clause 7.2.11 of CSA B620
- Contact us
Structural inspections authorization requirement
To perform the structural inspection, CSA B620 facilities must be authorized to do so on their Transport Canada Certificate of Registration. The following statement must appear in the "Conditions and limitations" section of your Certificate of Registration. The wording doesn't need to be exactly the same, as long as the meaning is preserved.
TC 423 highway tank trailers must be inspected every five years.
This registration includes structural inspection of TC 423 highway tank trailers.
Applying to perform structural inspections
If you would like to perform structural inspections of TC 423 highway tank trailers and the above statement doesn't appear on your Certificate of Registration, please contact us.
When applying to perform structural inspections, your email to the Engineering Services group must include:
- a statement that you want to add structural inspections to your scope of work
- your facility registration number (i.e., 25-xxxx)
- the structural inspection procedure present in your quality control manual, as per Clause 7.2.11 and Annex B.1.1.3 Section 12 Inspection and Testing of CSA B620
- the sample structural inspection report required as per Clause 7.3.1 and Annex B.1.1.3 Section 22 Exhibits of CSA B620
Please don't send a new application form or a copy of your quality control manual, only the documents requested above must be submitted.
Structural inspections as per Clause 7.2.11 of CSA B620
The manufacturer or assembler shall provide to the owner a procedure for the structural inspection referred to in Clause 7.2.11 of CSA B620. The procedure shall include a drawing identifying all critical joints and areas of high stress or stress concentration to be inspected.
7.2.11 Tank trailers shall be subjected to an inspection of all structural components, structural welds, structural components in spaces between or adjacent to compartments in compartmentalized tanks, and areas of high stress or stress concentration in the tank and frame for cracks and other defects as follows:
- prior to inspection, the tank shall be decontaminated as prescribed in Clause 7.1.3 of CSA B620;
- the jacketing and insulation shall be removed as necessary, or inspection ports in the jacketing and insulation shall be used to conduct the required inspection;
- areas to be inspected shall include but are not restricted to:
- points of attachment between the tank wall and frame components for the suspension system, upper coupler, and landing gear;
- points of attachment between the ring stiffeners and frame components for the suspension system, upper coupler, and landing gear;
- seams near the bottom centre of the tank;
- critical areas of shape transition such as the bottom of the circumferential seam on dual conic designs;
- structural compartments or connecting structures;
- discontinuities in the frame or tank wall;
- areas surrounding a centre bottom outlet; and
- any areas identified by the manufacturer or assembler in accordance with Clause 5.10.13 of CSA B620;
- welds in critical areas shall be inspected for cracks using dye penetrant or magnetic particle testing;
- following inspection, repair of any defects found, and subsequent re-inspection, the jacketing and insulation shall be replaced in a manner that will facilitate future inspection of critical areas; and
- following the inspection, a written report shall be completed by the inspection facility in accordance with Clause 7.3. The report shall include a drawing identifying all critical joints and high stress areas inspected.
The following letter shall indicate the type of inspection or test:
- "S" shall signify structural inspection
For periodic inspection and test intervals, please refer to Clause 7.1.1 of CSA B620.