TABLE 1 Measures of Environmental Performance


What It Measures



Permit Compliance

Compliance with applicable permits expressed as exceeding permit limits.

An essential measure—customers will look first to your compliance with permits

Taken alone, a narrow measure indicating that you are doing only what is required.

Toxic Release Inventory (TRI) Chemical Releases

Over 300 chemicals subject to release annual reporting requirements under SARAa Section 313.

Information on releases is widely available to the public; an effective way to communicate performance.

Does not cover all important chemicals or industries; focuses on release volume without accounting for differences in toxicity.

33/50 Chemicals

A subset of 17 of the TRI chemicals identified by the Environmental Protection Agency as priority candidates for voluntary reductions in releases by industry.

A more refined list of chemicals than TRI; companies participating in the 33/50 program and meeting goals will receive public credit.

Leaves out many important chemicals; not clear that a company not participating in the 33/50 program will receive special credit for these reductions.

Clean Air Act Toxics

189 chemicals listed in the Clean Air Act as air toxics subject to maximum achievable control technology (MACT) standards.

MACT standards will be extremely costly to meet. By reducing or eliminating releases, you avoid very high future costs.

Taken alone, like TRI, not a full measure of environmental performance; focuses only on air; creates risk of shifting problem from air to other media.

Risk-Weighted Releases

Toxic chemicals weighted by their relative toxicity.

A more realistic depiction of health and environmental effects than unweighted releases.

Toxicity data are frequently highly uncertain; risk-weighted approach has not been generally accepted by key customers—EPA, environmental groups.

Waste per Unit of Production

Percentage of production lost as waste; generally measured by weight.

A very broadly applicable measure that incorporates efficiency in use of resources as well as contaminant releases to the environment.

No priority established in term of type of wastes; absent other measures, creates an incentive to focus on high-volume, low-toxicity wastes.

The National Academies of Sciences, Engineering, and Medicine
500 Fifth St. N.W. | Washington, D.C. 20001

Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement