Irradiated

DOE-HDBK-1188-2006

99. IRRADIATED. Exposed to ionizing radiation. [Derived from NRC Glossary, ANSI N1.1]

The condition of reactor fuel elements and other materials in which atoms bombarded with nuclear

particles have undergone nuclear changes. [Derived from UI, MHE]

100. ISOTOPE. Any of two or more variations of an element in which the nuclei have the same number of

protons (i.e., the same atomic number) but different numbers of neutrons so that their atomic masses

differ. Isotopes of a single element possess almost identical chemical properties, but often different

physical properties (e.g., carbon-12 and -13 are stable, carbon-14 is radioactive). [Derived from

HPRH, EPA Terms, RHD]

101. LATENT CANCER FATALITIES (LCF). Deaths from cancer resulting from, and occurring some

time after, exposure to ionizing radiation or other carcinogens.

102. LEGAL-WEIGHT TRUCK. A truck that meets vehicle weight limits for U.S. Interstate Highways.

Under Federal regulations (23 CFR 658.17) the total loaded weight of a tractor-trailer combination is

limited to 80,000 pounds (34,874 kilograms). Some states allow heavier vehicles on highways within

the state.

Note: This specific terminology does not appear in the applicable Federal regulations.

[Derived from 23 CFR 658]

103. LIFE CYCLE COSTS.

1. All the anticipated costs associated with a project or program alternative throughout its life. This

includes costs from pre-operations through operations or to the end of the alternative. [DOE G

430.1-1]

2. All costs, except the cost of personnel occupying the facility, incurred from the time that a space

requirement is defined until that facility passes out of the government's hands. [DOE 6430.1A]

104. LOW-ENRICHED URANIUM (LEU). Uranium whose content of the fissile isotope uranium-235

has been increased through enrichment to more than 0.7 percent but less than 20 percent by weight.

Most nuclear power reactor fuel contains low-enriched uranium containing 3 to 5 percent uranium-

235. [Derived from 10 CFR 50.2 ]

105. LOWEST ACHIEVABLE EMISSION RATE (LAER). The emissions rate permitted for new

sources or major modifications of existing sources in areas that are not in attainment of National

Ambient Air Quality Standards (NAAQS). The LAER is defined on a case-by-case basis, according

to the regulations found in 40 CFR 51.165. [Derived from 40 CFR 51.165]

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