Population equivalent

Population equivalent or unit per capita loading, (PE), in waste-water treatment is the number expressing the ratio of the sum of the pollution load produced during 24 hours by industrial facilities and services to the individual pollution load in household sewage produced by one person in the same time.
For practical calculations, it is assumed that one unit equals to 54 grams of BOD per 24 hours.

[inhab/(unit/d)]

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