Which role is barred from designing a Class 4 system?

• A. The Inspector
• B. The Owner
• C. A Licensed Designer
• D. The Property Appraiser

Answer: (A)

The main idea is that designing a Class 4 on-site wastewater system requires licensed design expertise, and certain roles are kept separate to protect objectivity and safety. A Class 4 system is complex and must be planned by a licensed designer who has the training to create a plan that meets all code requirements and site conditions. An inspector, on the other hand, focuses on checking conformity to the approved plans and regulations during and after installation. Their job is to verify that what is built matches what was permitted, not to create the design itself. Allowing an inspector to design a system could create a conflict of interest and compromise safety and compliance, which is why the inspector is barred from designing a Class 4 system. The property appraiser isn’t involved in design decisions at all, and the owner can sometimes take on certain responsibilities, but for a complex Class 4 system, a licensed designer is the appropriate design professional.