Definitions for "BACKGROUND NOISE"
Electrical or chemical interferences with the signal coming from the detector of an analytical instrument. The analyte must create a signal in the detector which sufficiently overcomes these interferences in order to be detected. In the case of dioxin/furan analysis, the signal to noise ratio must be greater than 2.5 for all monitored analyte signals.
In an amplifier or other device that draws current, there is always some noise output in addition to the desired signal
The noise level in a space, which is a composite of sound from HVAC, equipment, activity noises, etc., from both near and far, but excluding specific sources of interest such as a person talking in an adjacent space (which would be considered the signal).
The result of electronic amplification of electronic current inherent in CCD cameras. Resulting images appear to be speckled with random dots like the snowy picture of a poor television picture.