Texas Wastewater Class B Practice Exam

The minimum pressure rating required for force mains and fittings is indeed 150 psi. This standard is established to ensure that the materials used in the construction of force mains can withstand the operational pressures typically encountered in wastewater systems.

Force mains transport wastewater under pressure, which is essential when gravity flow can't be used. The 150 psi rating provides a margin of safety against potential pressure surges and other operational stresses that can occur in the system.

While higher pressure ratings exist, such as 200 psi or 250 psi, they are not the minimum requirement, which is why those options are positioned above the standard threshold. The choice of 100 psi is also lower than what's required for the performance and safety of modern wastewater systems.