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Toxics Release Inventory (TRI) Program

TRI Supplemental Documentation

This metadata page contains reference information to support use and understanding of Toxics Release Inventory (TRI) data. Additional resources in the form of downloadable Excel files will be added as they are available. 


Active/Inactive Dates (xlsx)(44 K, 4/26/2019)  – List of TRI chemicals denoting the first and last year of required TRI reporting. This is equivalent to active and inactive data fields in the TRI database.

Core Chemicals (xlsx)(1 pg, 72 K, 12/7/2017) – Set of TRI chemicals (for 1988, 1991, 1995, 1998, 2000, 2001, 2011 and 2012) with consistent reporting requirements from a particular year to the current year. Using the core chemicals for analysis facilitates more accurate year-to-year comparisons. The set excludes chemicals added, deleted, or modified (i.e., threshold or definition changes) during the year range.

Chemicals by Health Effects (xlsx)(1 pg, 93 K, 12/7/2017) – List of TRI chemicals associated with certain health effects based on data contained within the TRI-Chemical Hazard Information Profiles database. Chemicals may be associated with 17 possible health effects including developmental, respiratory, and neurological. Chemicals are also flagged as carcinogens based on classification by the Occupational Safety and Health Administration (OSHA).

Chemicals by Categories of Interest (xlsx)(1 pg, 70 K, 12/7/2017) – List of TRI chemicals also covered by specific regulatory programs or classified by other properties.

  • Categories include Toxics Substance Control Act (TSCA) workplan chemicals; Hazardous Air Pollutants (HAPs); Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) chemicals; EPCRA Emergency Notification of Releases; Section 304 chemicals, CAA 112(r): Accidental Release Prevention; Persistent Bioaccumulative and Toxic (PBT) Chemicals; Metals; and Newly Added TRI Chemicals in 1995.

All Chemical Categories (xlsx)(1 pg, 155 K, 12/7/2017) – Spreadsheet containing all of the above information.


Industry Sector Categories (xlsx)(1 pg, 74 K, 2/16/2018)  – List of specific 3- or 4-digit NAICS codes that represent the majority of TRI-covered industry sectors and facilitate analysis at an industry sector scale. There are 29 categories and one catch all (999, other) to aggregate the 6-digit NAICS codes. The spreadsheet also provides details on code changes between the various NAICS standards (2002, 2007, 2012 and 2017) used by the TRI Program.


Pollution Prevention (P2) Codes (xlsx)(17 K, 10/31/2019)  – List of P2 codes that facilities may use for TRI reporting: Source Reduction Activity (W codes), Methods to Identify Source Reduction Activities (T codes), Estimated Annual Reduction Range (R codes), and Barriers to Implementing Pollution Prevention (B codes).

Waste Management Codes (xlsx)(1 pg, 17 K, 12/7/2017)  – List of codes used to identify the waste treatment applied on site to waste streams containing TRI chemicals and codes for identifying the energy recovery and recycling techniques used.

Transfer Codes (xlsx)(17 K, 11/1/2019)  – List of M codes by waste management method that facilities may use for quantities transferred off site for disposal or further management.