What is the main requirement for the diameter of the pass-thru hole or slot?

The main requirement for the diameter of the pass-thru hole or slot is that it must be equal to or greater than the inlet pipe diameter. This ensures proper flow dynamics within the septic system. The inlet pipe is designed to carry wastewater into the system, and if the pass-thru hole or slot is smaller than the inlet diameter, it could create a bottleneck, impeding flow and potentially leading to backups or system failures. Furthermore, maintaining this size helps to promote even distribution of flow, allowing the system to operate effectively and efficiently.

By adhering to the requirement that the pass-thru opening matches or exceeds the inlet pipe diameter, installers can ensure that the wastewater enters the system without restriction, which is crucial for the system's overall performance and longevity. Notably, the design considerations for the tank itself do not dictate a fixed size, nor is there a need for the pass-thru hole to simply be larger than the outlet pipe since the outlet serves a different function in the system. Thus, this requirement is pivotal for ensuring optimal operational standards in septic installations.