# Emergency Planning and Community Right-to-Know Act; Extremely Hazardous Substances List; Modification of Threshold Planning Quantity for Isophorone Diisocyanate
> **Rule** · Final rule. · Published 2003-09-08 · Effective 2003-10-08 · 68 FR 52978
## Document
- **Document number:** 03-22770
- **Category:** other
- **Federal Register citation:** 68 FR 52978
- **CFR reference:** 40 CFR 355
- **Publication date:** 2003-09-08
- **Effective date:** 2003-10-08
- **EPA docket:** FRL-7554-9
## Abstract

This rule amends the list of extremely hazardous substances (EHS) issued under the Emergency Planning and Community Right-to-Know Act (EPCRA) by changing the threshold planning quantity (TPQ) for isophorone diisocyanate (IPDI) from 100 pounds to 500 pounds.

## Source
- [Federal Register document](https://www.federalregister.gov/documents/2003/09/08/03-22770/emergency-planning-and-community-right-to-know-act-extremely-hazardous-substances-list-modification)
---
*AI Analytics · CC0 1.0*