The above sizing criteria:

a) All roof and surface water being excluded from the treatment system;
b) Kitchen waste disposal units not being connected to the foul drainage system serving the treatment system (if kitchen waste disposal units are intended to be used then consult MANTAIR
or relevant Licensed Contractor).

For Multiple Properties first use the above chart to determine the population requirement for each property. Then add together the population requirements of each property to arrive at the population size required for a simple system. For example, if a system is to serve two properties - one with 3 bedrooms and one with 4 bedrooms, the size required for a single system is therefore
5 + 7 = 12 P.E.