This method is used to determine suspended solids present in raw water, waste water and effluents by filtration through glass fibre filters. The lower limit of the determination is about 2mg/l. No upper limit has been established. Water samples are not always stable which means that the content of suspended solids depends on storage time, means of transportation, pH value and other circumstances. Results obtained with unstable samples need to be treated with caution. Floating oil and other immiscible organic liquids will interfere (see EN 872, Annex A). This method complies with EN 872.