What material should vent pipes be made of in active soil depressurization systems?

In active soil depressurization systems, it is essential that vent pipes are made of materials that can withstand varying underground conditions while effectively managing airflow. Schedule 40 PVC and ABS are commonly used because they are both durable, resistant to corrosion, and suitable for below-ground applications. These materials provide sufficient structural integrity to handle the pressures related to soil gas movement, such as radon, while preventing any leakage that could undermine the efficacy of the system.

Additionally, PVC and ABS are relatively lightweight and easy to work with, facilitating installation. They are also non-reactive to the gases they are intended to vent, ensuring that they will not degrade over time in the presence of these substances. In contrast, other materials such as metal may corrode, and polyethylene—while occasionally used—does not have the same ratings for pressure handling as Schedule 40 PVC or ABS. Fiberglass or glass, while strong, often lacks the flexibility and practical benefits that PVC and ABS provide for regular venting needs in these systems.