The outlet tee must have an approved effluent filter. What type of tee is being referred to?

The correct answer highlights the significance of the outlet tee in septic system design, specifically emphasizing its role in treating effluent before it is released into the drain field. An approved effluent filter is installed on the outlet tee to capture solid particles and prevent them from entering the drain field, which helps to maintain the system's overall function and longevity.

This type of tee is essential because it plays a pivotal role in ensuring that only treated, clear effluent is discharged. By filtering out harmful solids, the outlet tee helps protect the drain field from clogging and premature failure, thus improving the system's efficiency and reducing maintenance costs. Properly functioning outlet tees with effective filters are critical in safeguarding both the environment and public health, as they minimize the risk of groundwater contamination. This understanding is foundational for anyone involved in the installation or maintenance of commercial septic systems.