1.3 On-site tests
To give you a flavour of the breadth of this topic, we will look at the measurement of a selection of the key chemical species or parameters relevant to water quality, these are:
- chemical oxygen demand
- dissolved oxygen
- electrical conductivity.
In the parts that follow these parameters are being used as exemplars to illustrate a particular field technique. It's important to stress that there are other ways of measuring a particular parameter on site, e.g. pH can be measured by test strip, but we're only considering it in the context of a pH probe; likewise there are colourimetric and titrimetric methods for the determination of dissolved oxygen available in addition to the electrochemical method described here.