A Major Non-Conformity is an indication or judgment that a process, product, or service has not met all the requirements and will likely impact the user's ability to use the product.

Major sources are defined by the Clean Air Act as those stationary facilities that emit or have the potential to emit 10 tons of any one toxic Air Pollutant or 25 tons of more than

Mammals (class Mammalia) are a clade of endotherms that are distinguishable from reptiles and birds by the possession of the mammalian auditory ossicles, mammary glands, and a neocortex.

Management indicator --->stressor indicator

A Management System is an organizational structure which concerns policies, objectives, principles, organizational authority, responsibilities, accountability, and implementation plan for conducting work and producing items and services.

A Management Systems Review (MSR) is a qualitative assessment of an organization's data collection operation or program used to establish whether the organization"s prevailing quality system, i.e., quality management structure, policies, practices, and procedures, is adequate for ensuring that the type and quality of data needed are obtained.

The Matrix is the material of which the sample is composed or the substrate containing the analyte of interest, such as drinking water, waste water, air, soil/sediment, biological material, etc. It is also called medium or media.

A Matrix Spike Duplicate is a sample prepared simultaneously as a split with the matrix spike sample with each specimen being spiked with identical, known concentrations of targeted analyte.

A Matrix Spike Sample is a test specimen prepared by adding a known concentration of the target analyte to a specified amount of a specific homogenized specimen where an estimate of the target concentration is available and subjected to the entire analytical protocol.