To determine the minimum size of an aerobic treatment plant, which factor must be considered?

To determine the minimum size of an aerobic treatment plant, it is essential to consider the daily sewage volume generated by the household. The daily sewage volume is influenced by the number of bedrooms in the home since it is generally accepted that more bedrooms correlate with a higher occupancy and thus more wastewater produced. The sizing of an aerobic treatment plant must accommodate the anticipated volume of wastewater to ensure effective treatment and compliance with health and safety regulations.

While aeration volume is important for the operation of an aerobic treatment system and the soil acceptance rate is crucial for determining where effluent can be safely disposed of, both do not directly correlate with the sizing based purely on the household's wastewater output. Similarly, knowing the number of bedrooms as a proxy for daily sewage volume is a fundamental aspect of sizing these systems, making it the key factor in this scenario.