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Water sampling

Water is essential for life, but for many people the quality of water available may be poor. Analysis of a water supply may be required to find out whether the water is safe to drink or whether it needs to be treated before consumption. Methods of analysing the quality of water are discussed in other films in this series. It is just as important, however, to ensure that the samples of water tested are representative of the water supply as a whole. Water sampling is therefore as important an activity as the process of water analysis and is the subject of this film.