Interpretation Response #21-0020
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: Transport Canada, Ontario Region
Individual Name: Brent Grice
Location State: ON Country: CA
View the Interpretation Document
Response text:
October 22, 2021
Mr. Brent Grice
Dangerous Goods Inspector
Transport Canada, Ontario Region
4900 Yonge Street-3rd Floor
North York, Ontario M2N 6A5
Canada
Reference No. 21-0020
Dear Mr. Grice:
This letter is in response to your March 2, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to rejection criteria during the inspection of Department of Transportation (DOT) Specification 51 portable tanks.
We have paraphrased and answered your questions as follows:
Q1. You ask what the rejection criteria is for a DOT Specification 51 portable tank should a reduction in wall thickness be found during an inspection.
A1. If a DOT Specification 51 portable tank is found to have a reduction in wall thickness during an inspection and it is verified by appropriate measurement, the wall thickness may not fall below the minimum thickness (i.e., the manufactured thickness minus any applicable corrosion allowance). If it does, the inspector may determine such findings to be evidence of an "unsafe condition."
Q2. You ask how a person should determine the minimum thickness of a DOT Specification 51 portable tank since the minimum thickness is not required to be marked on the name plate.
A2. If a DOT Specification 51 portable tank is not marked with the minimum wall thickness, the thickness listed on the manufacturer's data report—minus any applicable corrosion allowance—may be used as the minimum thickness of the portable tank.
Q3. You ask whether thickness readings that are below the thicknesses indicated on the manufacturer's data report—minus any applicable corrosion allowance—meet the rejection criteria of § 180.605(i) as evidence of an "unsafe condition."
A3. The answer is yes. If thickness readings are below the thicknesses indicated on the manufacturer's data report—minus any applicable corrosion allowance—the inspector may determine such findings to be evidence of an "unsafe condition" in accordance with § 180.605(i). See answer A1.
I hope this information is helpful. Please contact us if we can be of further assistance.
Sincerely,
T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division
180.605(i)