(redirected from Nephelometric turbidity units)
Also found in: Dictionary, Thesaurus, Medical.
Related to Nephelometric turbidity units: nephelometry


(analytical chemistry)
Measure of the clarity of an otherwise clear liquid by using colorimetric scales.
Cloudy or hazy appearance in a naturally clear liquid caused by a suspension of colloidal liquid droplets or fine solids.
The formation of disks centered on stars in long-exposure photographs as a result of light scattering by grains in the emulsion.
Any condition of the atmosphere which reduces its transparency to radiation, especially to visible radiation.



the capacity of an optically nonuniform medium to scatter light passing through it (see). The extinction coefficient is a quantitative characterization of turbidity and is given by the equation.

τ ═ (l/I) ln (I0/I)

where I0 and I are the intensities of a light beam before and after passage through a layer of the medium of thickness l. Turbidity is determined by methods of nephelometry and turbidimetry.

References in periodicals archive ?
All influent turbidity samples taken were >1,000 Nephelometric Turbidity Units (NTUs).
Three turbidity measurements were made on each aliquot, in nephelometric turbidity units (NTU), using a Hath[TM] turbidimeter.
The measurement is recorded in nephelometric turbidity units, or NTUs.