Fig. 5 presents the values of the quotient ‘‘working capacity of chambers used”/‘‘working designed capacity of chambers” for sys- tems in Marszów and for 20 systems covered by the Review. The value of the ‘‘working designed capacity of the chambers” was cal- culated by multiplying the number of chambers by the working capacity of the chamber. The ‘‘working capacity of the chambers used” was calculated by multiplying the weekly biological capacity of the biological plant for the duration of the intensive phase in weeks. When calculating the weekly volume throughput, 52 work- ing weeks were accepted in the year and the average annual den- sity of the undersized fraction of 650 kg/m3.