Glossary N
The Environmental Glossary. Letter N +++ Popular Articles: 'Nitrogen oxides', 'Noise regulation', 'National Ambient Air Quality Standards (NAAQS):'
A Nonattainment Area is a region in which the level of a Criteria Air Pollutant is higher than allowed by the federal NAAQS.
A Nonbiodegradable is Substance that cannot be broken down in the environment by natural processess. See biodegradable.
Nonparametric Tests are all studies involving ranked data, i.e., data that can be put in order and used when there is no assumption that the population has a normal distribution or when the population is known to have low and high values and valuable in detecting population differences when certain assumptions are not satisfied.
Nonpoint source are the large or dispersed land areas such as crop fields, streets, and lawns that Discharge pollutants into the environment over a large area. Compare point source.
A Nonpoint Source Pollution is "Diffuse” pollution, generated from large areas with no particular point of pollutant origin, but rather from many individual places.
A Nonrenewable resource is a natural resource from the Earth that exists in limited supply, like oil or coal. Once this supply is used up, the resource is gone forever.
A Nonroad mobile sources is a Mobile sources not found on roads and highways (e.g., airplanes, trains, lawn mowers, construction vehicles, farm machinery).