SPECTROPHOTOMETRY OVERVIEW Spectrophotometry is a well-established analytical method, which has been used for decades in chemistry, physics, biochemistry, and chemical engineering for quantitative analyses. A light source and sensor are used to measure the intensity of light passing through a water sample…
Specific ultraviolet absorbance (SUVA) provides a general characterization of the nature of natural organic matter (NOM) in a water sample and is typically performed for the purpose of determining disinfection by-product (DBP) formation potential. SUVA is calculated by dividing the…
UV254, TOC, DOC, BOD and COD all provide measures of different aspects of the organic content in a water sample. Each of these parameters possesses a certain bias due to the nature of the particular test method: ABSORBANCE AT 254…
The relationship between absorbance and concentration is defined by Beer-Lambert Law (or Beer’s Law). Beer’s Law states that the absorbance of light absorbing matter in water is directly proportional to its concentration, expressed by the following equation: A = ε•b•c…
When looking at source water monitoring for drinking water treatment, the terms colour and natural organic matter (NOM) are often interchanged. This may be due to organic matter, such as humic acids, causing visible colour in surface water. However, its…
According to Beer’s Law, absorbance is directly proportional to the path length of the UV light through the water sample. Absorbance is given by the following equation: UVA = ε•b•c where ε is the molar absorbtivity of the particular type…
When it comes to real-time water quality analysis, there two primary forms of instruments to choose from; a bypass style cabinet instrument or a submersible probe instrument. So what is the different between these two forms and how do you…
UV ABSORBANCE The UV absorbance is calculated as a relative measure of the amount of light absorbed by a water sample compared with the amount of light absorbed by a pure water sample. The sample water measurement is actually divided…
UVA and UVT are essentially just different representations of the same physical phenomenon. They can be related by a simple mathematical expression which indicates an inverse logarithmic relationship between UVA and UVT. UVA = 2 – log10 UVT Since UVT and…
Ultraviolet transmission or UV transmittance (UVT) is a water quality measurement. The method works by measuring the amount of UV light, typically at 254 nm, that is able to pass through a water sample of a given path length. It…
