Criteria Pollutant

DOE-HDBK-1188-2006

"Contact-handled transuranic waste" means transuranic waste with a surface dose rate not greater

than 200 millirem per hour. [WIPP LWA]

(See remote-handled waste.)

43. CRITERIA POLLUTANT. An air pollutant that is regulated by National Ambient Air Quality

Standards (NAAQS). The Environmental Protection Agency must describe the characteristics and

potential health and welfare effects that form the basis for setting, or revising, the standard for each

regulated pollutant. Criteria pollutants include sulfur dioxide, nitrogen dioxide, carbon monoxide,

ozone, lead, and two size classes of particulate matter, less than 10 micrometers (0.0004 inch) in

diameter, and less than 2.5 micrometers (0.0001 inch) in diameter. New pollutants may be added to,

or removed from, the list of criteria pollutants as more information becomes available. (See National

Ambient Air Quality Standards.)

Note: Sometimes pollutants regulated by state laws are also called criteria pollutants.

[Derived from EPA Terms]

44. CRITICAL HABITAT. Habitat essential to the conservation of an endangered or threatened species

that has been designated as critical by the U.S. Fish and Wildlife Service or the National Marine

Fisheries Service following the procedures outlined in the Endangered Species Act and its

implementing regulations (50 CFR 424). (See endangered species and threatened species.)

The lists of Critical Habitats can be found in 50 CFR 17.95 (fish and wildlife), 50 CFR 17.96

(plants), and 50 CFR 226 (marine species).

[Derived from 50 CFR 402.02, 50 CFR 424.02(d)]

45. CRITICAL ORGAN. The body organ receiving a radionuclide or radiation dose that would result in

the greatest overall damage to the body. Specifically, that organ in which the dose equivalent would

be most significant due to a combination of the organ's radiological sensitivity and the dose distribution

throughout the body. [Derived from HPRH, ANSI N1.1]

46. CRITICALITY. The condition in which a system is capable of sustaining a nuclear chain reaction.

[Derived from DOE 6430.1A, DOE 5480.30, DOE Glossary]

Chain reaction: A reaction that initiates its own repetition. In nuclear fission, a chain reaction occurs

when a neutron induces a nucleus to fission and the fissioning nucleus releases one or more neutrons

which induce other nuclei to fission. [Derived from UI]

Critical Mass: The smallest mass of fissionable material that will support a self-sustaining nuclear

chain reaction. [Derived from UI]

A-11