Pipeline Interpretations
The Pipeline and Hazardous Materials Safety Administration, Office of Pipeline Safety provides written clarifications of the Regulations (49 CFR Parts 190-199) in the form of interpretation letters. These letters reflect the agency's current application of the regulations to the specific facts presented by the person requesting the clarification. Interpretations are one form of Guidance provided by this office.
Interpretations do not create legally-enforceable rights or obligations and are provided to help the public understand how to comply with the regulations.
This office regularly reviews interpretations on this site for accuracy and applicability. Interpretation letters are published here to provide the public with a greater awareness and understanding of the regulations. Letters of interpretation which are found to be inaccurate or no longer applicable are removed and may be revised and reissued if warranted. Letters which do not appear on this website may no longer be valid.
We welcome feedback from the pipeline safety community to ensure the most recent and accurate letters of interpretation are provided here. Questions or concerns about a specific letter or topic should be directed to the Office of Pipeline Safety.
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