Extremely Hazardous Substances (EHSs) are substances listed on the EPA List of Lists. These substances in quantities at or above the Threshold Planning Quantity (TPQ) require certain emergency planning activities to be conducted. To determine if the substance you have is reportable as an EHS please refer to the Safety Data Sheet and List of Lists.
Substances that are highly toxic or explosive have the following lower reporting levels (LRL):
Liquids: 5 gallons or more
Solids: 10 pounds or more
Gases: 20 cubic Feet or more
Non-Sealed Radioactive: Reportable at any amount
All other substances have the following Upper Reporting Levels (URL):
Liquids: 500 gallons or more
Solids: 500 pounds or more
Non-liquified gases: 500 cubic feet or more
Liquefied gases: 500 gallons or more
If you have additional questions, please submit a Help Desk ticket or call the Hazardous Substance Information Hotline 503-378-6835 or 800-454-6125.