What is the difference between Tier I and Tier II?

Facilities covered by the Emergency Planning and Community Right-to-Know Act (EPCRA) Hazardous Chemical Storage Reporting Requirements must submit an emergency and hazardous chemical inventory form to the Local Emergency Planning Committee (LEPC), the State Emergency Response Committee (SERC) and the local fire department annually. Facilities provide either a Tier I or Tier II form. Most states require the Tier II form.

The Tier I form categorizes chemicals by hazard category. This form requires the maximum amount of chemicals for each category, the average daily amount of chemicals for each category, the greatest number of days the chemical was on-site, and the general location of the chemicals in the facility.

The Tier II form goes into more detail about each chemical and requires:

• Chemical or mixture description, including physical and health hazards
• Maximum amount of each chemical or mixture on site on any single day during the reporting period
• Average daily amount of each chemical or mixture on site during the reporting period
• Number of days the chemical was on site
• Description of the manner in which each chemical was stored and its location