Hazardous Liquid Integrity Management
HL IM Menu
This site is administered by the Pipeline and Hazardous Materials Safety Administration (PHMSA). It provides information concerning Liquid Pipeline Integrity Management in High Consequence Areas for Hazardous Liquid Operators (49 CFR Parts 195.450 and .452), commonly referred to as the “Liquid IM Rule.”
The Liquid IM Rule specifies how pipeline operators must identify, prioritize, assess, evaluate, repair and validate the integrity of hazardous liquid pipelines that could, in the event of a leak or failure, affect High Consequence Areas (HCAs) within the United States. HCAs include: population areas; areas containing drinking water and ecological resources that are unusually sensitive to environmental damage; and commercially navigable waterways.
For an overview of the progress being made under the Liquid IM Rule, please see our Performance Measures page. There you will find graphs and charts, which depict progress and other aspects of rule implementation. You will also find a link to the tabulated annual submissions provided by pipeline operators in accordance with this rule.
Other links on the left provide a great deal of additional information, including an operator IM process flowchart and a fact sheet that summarizes key requirements of the Liquid IM Rule; details of the Liquid IM Rule itself; a glossary of related terminology; FAQs; and other information useful in more fully understanding the Liquid IM Rule.
When continuing implementation of the Liquid IM Rule results in rule revisions, new interpretations, or expanded clarifications, this site is updated to reflect those developments.